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Real Estate Dispositions, Held for Sale and Impairment Charges - Additional Information (Detail) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 USD ($) property | Jun. 30, 2017 USD ($) property | Mar. 31, 2017 USD ($) property | Sep. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) property | Sep. 30, 2016 USD ($) property | Dec. 31, 2016 property
Real Estate Properties [Line Items] |  |  |  |  |  |  |
Number of properties sold |  |  |  |  | 4 |  |
Number of real estate properties, held for sale | 0 |  |  |  | 0 |  |
Impairment charge | $ | $ 0 | $ 300 |  | $ 1,786 | $ 3,999 | $ 2,016 |
Number of impaired assets, held and used | 0 | 0 | 2 |  | 0 |  |
Impairment of asset held and used | $ |  |  | $ 3,700 |  |  |  |
Number of impaired assets sold, held and used |  | 1 |  |  |  |  |
Gain (loss) on sale of real estate, net | $ | $ 1 |  |  | $ (24) | $ 3,993 | (24) |
Impairment charge for assets held for sale | $ |  |  |  |  |  | 2,000 |
Number of impaired properties reclassified to held and used | 1 |  |  |  | 1 |  |
Hazelwood, Missouri and Franklin, New Jersey |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |
Number of real estate properties, held for sale |  |  |  |  |  |  | 2
Disposed of by sale |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |
Number of properties sold |  |  |  |  | 4 |  |
Impairment charge | $ |  |  |  |  | $ 3,999 | $ 700 |
Gain (loss) on sale of real estate, net | $ |  |  |  |  | $ 3,993 |  |
Disposed of by sale | Hazelwood, Missouri and Franklin, New Jersey |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |
Number of properties sold |  |  |  |  | 2 |  |
Disposed of by sale | Undisclosed location |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |
Gain (loss) on sale of real estate, net | $ | $ 1 |  |  |  |  |  |
Held for sale |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |
Gain (loss) on sale of real estate, net | $ |  | $ (1,800) |  |  |  |  |
Number of impaired assets sold, held for sale | 4 |  |  |  | 4 |  |
Number of impaired assets |  |  |  |  |  | 5 |

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- Definition Number of Impaired Assets, Held and Used + References No definition available. + Details
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- Definition Number of Impaired Assets, Held-for-use Reclassified from Held-for-sale + References No definition available. + Details
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- Definition Number of Impaired Assets Sold, Held for Sale + References No definition available. + Details
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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- Definition The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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