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Real Estate and Intangible Assets - Summary of Lease on Property (Detail) $ in Thousands | 9 Months Ended
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Sep. 30, 2016 USD ($) ft² property option | Sep. 30, 2015 USD ($) ft² property option
Real Estate Properties [Line Items] |  |
Number of leased properties | property | 7 |
Number of properties acquired | property | 2 | 5
Square Footage (unaudited) | ft² |  | 203,538
Renewal Options | option |  | 2
Renewal options period |  | 5 years
Annualized GAAP Rent |  | $ 3,183
Tenant Improvement |  | 1,530
Leasing Commissions |  | $ 722
Maple Heights, OH [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date | Jun. 01, 2016 |
Square Footage (unaudited) | ft² | 40,606 |
Renewal Options | option | 2 |
Renewal options period | 3 years |
Annualized GAAP Rent | $ 109 |
Tenant Improvement | 0 |
Leasing Commissions | $ 34 |
Lease term | 5 years 2 months 12 days |
Bolingbrook, IL [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date | Jul. 01, 2016 |
Square Footage (unaudited) | ft² | 13,816 |
Renewal Options | option | 1 |
Renewal options period | 5 years |
Annualized GAAP Rent | $ 70 |
Tenant Improvement | 69 |
Leasing Commissions | $ 28 |
Lease term | 7 years 2 months 12 days |
Richmond, Virginia [Member] |  |
Real Estate Properties [Line Items] |  |
Square Footage (unaudited) | ft² | 42,213 |
Annualized GAAP Rent | $ 228 |
Tenant Improvement | 0 |
Leasing Commissions | $ 0 |
Maple Heights, OH One [Member] |  |
Real Estate Properties [Line Items] |  |
Square Footage (unaudited) | ft² | 180,000 |
Annualized GAAP Rent | $ 530 |
Tenant Improvement | 60 |
Leasing Commissions | $ 0 |
Indianapolis, IN [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Jan. 01, 2015
Square Footage (unaudited) | ft² |  | 3,546
Annualized GAAP Rent |  | $ 64
Tenant Improvement |  | 64
Leasing Commissions |  | $ 28
Lease term |  | 8 years 3 months 18 days
Indianapolis, IN One [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Feb. 01, 2015
Square Footage (unaudited) | ft² |  | 8,275
Annualized GAAP Rent |  | $ 124
Tenant Improvement |  | 0
Leasing Commissions |  | $ 0
Lease term |  | 3 years
Raleigh, NC [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Feb. 01, 2015
Square Footage (unaudited) | ft² |  | 58,926
Annualized GAAP Rent |  | $ 711
Tenant Improvement |  | 0
Leasing Commissions |  | $ 144
Lease term |  | 5 years 6 months
Raleigh, NC One [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Feb. 01, 2015
Square Footage (unaudited) | ft² |  | 21,300
Annualized GAAP Rent |  | $ 239
Tenant Improvement |  | 100
Leasing Commissions |  | $ 32
Lease term |  | 5 years 6 months
Columbus, OH [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Dec. 01, 2016
Square Footage (unaudited) | ft² |  | 9,484
Annualized GAAP Rent |  | $ 1,246
Tenant Improvement |  | 142
Leasing Commissions |  | $ 29
Lease term |  | 7 years 1 month 6 days
Burnsville, MN [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date | Dec. 01, 2016 |
Square Footage (unaudited) | ft² | 12,663 |
Renewal Options | option | 1 |
Renewal options period | 5 years |
Annualized GAAP Rent | $ 143 |
Tenant Improvement | 0 |
Leasing Commissions | $ 104 |
Lease term | 5 years 3 months 18 days |
South Hadley, MA [Member] |  |
Real Estate Properties [Line Items] |  |
Square Footage (unaudited) | ft² | 150,000 |
Annualized GAAP Rent | $ 288 |
Tenant Improvement | 0 |
Leasing Commissions | $ 7 |
Raleigh NC Two [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Aug. 01, 2015
Square Footage (unaudited) | ft² |  | 86,886
Renewal Options | option |  | 2
Renewal options period |  | 5 years
Annualized GAAP Rent |  | $ 534
Tenant Improvement |  | 800
Leasing Commissions |  | $ 398
Lease term |  | 12 years 4 months 24 days
Indianapolis, IN Two [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Aug. 01, 2015
Square Footage (unaudited) | ft² |  | 6,903
Annualized GAAP Rent |  | $ 111
Tenant Improvement |  | 64
Leasing Commissions |  | $ 16
Lease term |  | 3 years
Baytown, TX [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Sep. 18, 2015
Square Footage (unaudited) | ft² |  | 6,791
Renewal Options | option |  | 2
Renewal options period |  | 5 years
Annualized GAAP Rent |  | $ 132
Tenant Improvement |  | 360
Leasing Commissions |  | $ 71
Lease term |  | 7 years
Indianapolis, IN Three [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date |  | Oct. 01, 2015
Square Footage (unaudited) | ft² |  | 1,427
Annualized GAAP Rent |  | $ 22
Tenant Improvement |  | 0
Leasing Commissions |  | $ 4
Lease term |  | 3 years
Bolingbrook, IL (2) [Member] |  |
Real Estate Properties [Line Items] |  |
Lease Commencement Date | Jan. 02, 2017 |
Square Footage (unaudited) | ft² | 20,719 |
Annualized GAAP Rent | $ 107 |
Tenant Improvement | 204 |
Leasing Commissions | $ 48 |
Salt Lake City UT [Member] |  |
Real Estate Properties [Line Items] |  |
Renewal Options | option |  | 1
Renewal options period |  | 5 years

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- Definition Area of leased property. + References No definition available. + Details
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- Definition Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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