Quarterly report pursuant to Section 13 or 15(d)

Real Estate and Intangible Assets - Fair Value of Acquired Assets and Liabilities Assumed (Detail)

v2.4.0.8
Real Estate and Intangible Assets - Fair Value of Acquired Assets and Liabilities Assumed (Detail) (USD $)
In Thousands, unless otherwise specified
9 Months Ended
Sep. 30, 2014
Sep. 30, 2013
Business Acquisition [Line Items]    
Total Purchase Price $ 93,711 $ 105,638
Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 5,781 6,994
Above Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 387 336
Below Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired (19) (1,168)
Discount on Assumed Debt [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired (249)  
Allen, TX [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 5,525 15,150
Allen, TX [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 218 1,499
Allen, TX [Member] | Above Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   336
Allen, TX [Member] | Discount on Assumed Debt [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired (72)  
Colleyville, TX [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 4,523  
Colleyville, TX [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 181  
Colleyville, TX [Member] | Below Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired (6)  
Colleyville, TX [Member] | Discount on Assumed Debt [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired (59)  
Rancho Cordova, CA [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 8,225  
Rancho Cordova, CA [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 278  
Coppell, TX [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 5,838  
Coppell, TX [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 230  
Coppell, TX [Member] | Discount on Assumed Debt [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired (118)  
Columbus, OH [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 11,800  
Columbus, OH [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 990  
Columbus, OH [Member] | Above Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 261  
Taylor, PA [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 39,000  
Taylor, PA [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 2,870  
Aurora, CO [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 8,300  
Aurora, CO [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 282  
Indianapolis, IN [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price 10,500  
Indianapolis, IN [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 732  
Indianapolis, IN [Member] | Above Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 126  
Indianapolis, IN [Member] | Below Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired (13)  
Egg Harbor Township, NJ [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price   5,650
Egg Harbor Township, NJ [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   259
Vance, AL [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price   13,388
Vance, AL [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   627
Blaine, MN [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price   14,450
Blaine, MN [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   816
Austin, Texas [Member]
   
Business Acquisition [Line Items]    
Total Purchase Price   57,000
Austin, Texas [Member] | Customer Relationships [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   3,793
Austin, Texas [Member] | Below Market Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   (1,168)
Land [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 11,827 8,173
Land [Member] | Allen, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 874 2,699
Land [Member] | Colleyville, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 1,277  
Land [Member] | Rancho Cordova, CA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 752  
Land [Member] | Coppell, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 1,448  
Land [Member] | Columbus, OH [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 990  
Land [Member] | Taylor, PA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 3,102  
Land [Member] | Aurora, CO [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 2,882  
Land [Member] | Indianapolis, IN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 502  
Land [Member] | Egg Harbor Township, NJ [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   1,627
Land [Member] | Vance, AL [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   457
Land [Member] | Blaine, MN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   1,060
Land [Member] | Austin, Texas [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   2,330
Building [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 54,623 64,768
Building [Member] | Allen, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 3,509 5,758
Building [Member] | Colleyville, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 2,307  
Building [Member] | Rancho Cordova, CA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 5,898  
Building [Member] | Coppell, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 3,221  
Building [Member] | Columbus, OH [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 6,080  
Building [Member] | Taylor, PA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 24,449  
Building [Member] | Aurora, CO [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 3,825  
Building [Member] | Indianapolis, IN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 5,334  
Building [Member] | Egg Harbor Township, NJ [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   2,735
Building [Member] | Vance, AL [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   9,721
Building [Member] | Blaine, MN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   9,347
Building [Member] | Austin, Texas [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   37,207
Tenant Improvements [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 4,721 11,263
Tenant Improvements [Member] | Allen, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 125 2,187
Tenant Improvements [Member] | Colleyville, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 117  
Tenant Improvements [Member] | Rancho Cordova, CA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 278  
Tenant Improvements [Member] | Coppell, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 128  
Tenant Improvements [Member] | Columbus, OH [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 1,937  
Tenant Improvements [Member] | Taylor, PA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 956  
Tenant Improvements [Member] | Aurora, CO [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 92  
Tenant Improvements [Member] | Indianapolis, IN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 1,088  
Tenant Improvements [Member] | Egg Harbor Township, NJ [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   282
Tenant Improvements [Member] | Vance, AL [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   808
Tenant Improvements [Member] | Blaine, MN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   1,172
Tenant Improvements [Member] | Austin, Texas [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   6,814
In-Place Leases [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 11,590 10,659
In-Place Leases [Member] | Allen, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 598 1,525
In-Place Leases [Member] | Colleyville, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 486  
In-Place Leases [Member] | Rancho Cordova, CA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 473  
In-Place Leases [Member] | Coppell, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 636  
In-Place Leases [Member] | Columbus, OH [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 823  
In-Place Leases [Member] | Taylor, PA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 6,171  
In-Place Leases [Member] | Aurora, CO [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 413  
In-Place Leases [Member] | Indianapolis, IN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 1,990  
In-Place Leases [Member] | Egg Harbor Township, NJ [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   558
In-Place Leases [Member] | Vance, AL [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   1,097
In-Place Leases [Member] | Blaine, MN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   1,361
In-Place Leases [Member] | Austin, Texas [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   6,118
Leasing Costs [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 5,050 4,613
Leasing Costs [Member] | Allen, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 273 1,146
Leasing Costs [Member] | Colleyville, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 220  
Leasing Costs [Member] | Rancho Cordova, CA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 546  
Leasing Costs [Member] | Coppell, TX [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 293  
Leasing Costs [Member] | Columbus, OH [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 719  
Leasing Costs [Member] | Taylor, PA [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 1,452  
Leasing Costs [Member] | Aurora, CO [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 806  
Leasing Costs [Member] | Indianapolis, IN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired 741  
Leasing Costs [Member] | Egg Harbor Township, NJ [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   189
Leasing Costs [Member] | Vance, AL [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   678
Leasing Costs [Member] | Blaine, MN [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   694
Leasing Costs [Member] | Austin, Texas [Member]
   
Business Acquisition [Line Items]    
Fair value of acquired assets related to the properties acquired   $ 1,906