v3.8.0.1

Summary of Significant Accounting Policies - Schedule Showing Reduction of Carrying Value of Impaired Real Estate Assets to Estimated Fair Value (Detail) - USD ($) $ in Thousands | Dec. 31, 2017 | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Significant Accounting Policies [Line Items] |  |  |
Investments in rental property accounted for using the operating method, net of accumulated depreciation | $ 2,227,758 |  | $ 1,684,971
Intangible lease assets, net | 242,659 |  | 168,121
Leasing fees, net | 13,554 |  | 11,329
Intangible lease liabilities, net | $ (81,744) |  | $ (47,871)
Carrying Amount |  |  |
Significant Accounting Policies [Line Items] |  |  |
Investments in rental property accounted for using the operating method, net of accumulated depreciation |  | $ 16,159 |
Intangible lease assets, net |  | 1,263 |
Leasing fees, net |  | 123 |
Intangible lease liabilities, net |  | (101) |
Impaired real estate assets (liabilities), net |  | 17,444 |
Allocation of impairment |  |  |
Significant Accounting Policies [Line Items] |  |  |
Investments in rental property accounted for using the operating method, net of accumulated depreciation |  | (2,401) |
Intangible lease assets, net |  | (204) |
Leasing fees, net |  | (16) |
Intangible lease liabilities, net |  | 13 |
Impaired real estate assets (liabilities), net |  | (2,608) |
Net Carrying Amount |  |  |
Significant Accounting Policies [Line Items] |  |  |
Investments in rental property accounted for using the operating method, net of accumulated depreciation |  | 13,758 |
Intangible lease assets, net |  | 1,059 |
Leasing fees, net |  | 107 |
Intangible lease liabilities, net |  | (88) |
Impaired real estate assets (liabilities), net |  | $ 14,836 |

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- Definition Impaired real estate assets (liabilities), net. + References No definition available. + Details
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- Definition Significant accounting policies. + References No definition available. + Details
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- Definition Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life. + References No definition available. + Details
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- Definition This element represents costs incurred by the lessor that are (a) costs to originate a lease incurred in transactions with independent third parties that (i) result directly from and are essential to acquire that lease and (ii) would not have been incurred had that leasing transaction not occurred and (b) certain costs directly related to specified activities performed by the lessor for that lease. Those activities are: evaluating the prospective lessee's financial condition; evaluating and recording guarantees, collateral, and other security arrangements; negotiating lease terms; preparing and processing lease documents; and closing the transaction. This element is net of accumulated amortization. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=77902619&loc=d3e40246-112709 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=77913719&loc=d3e40879-112712 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=77902619&loc=d3e40588-112709 + Details
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(d)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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