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Real Estate Dispositions, Held for Sale, and Impairment Charges - Components of Operating Income from Real Estate and Related Assets Disposed (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating expense | $ 20,405 | $ 15,867 | $ 14,357 | $ 17,708 | $ 13,733 | $ 15,172 | $ 13,433 | $ 13,257 | $ 68,337 | $ 55,595 | $ 50,965
Impairment of real estate |  |  |  |  |  |  |  |  | 4,000 |  |
Gain (loss) on sale of real estate, net |  | $ 1 | $ (1,800) |  |  |  |  |  | 3,993 | 242 | 1,538
Real Estate Asset Disposal |  |  |  |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating revenue |  |  |  |  |  |  |  |  | 1,280 | 2,569 | 2,958
Operating expense |  |  |  |  |  |  |  |  | 4,449 | 1,883 | 1,192
Other income (expense), net |  |  |  |  |  |  |  |  | 3,831 | (403) | (922)
Income from real estate and related assets sold |  |  |  |  |  |  |  |  | $ 662 | $ 283 | $ 844

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- Definition Disposal Group, Including Discontinued Operation, Other Income (Expense) + References No definition available. + Details
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- Definition Income loss from real estate and related assets held for sale. + References No definition available. + 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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- Definition The charge against earnings in the period to reduce the carrying amount of real property to fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2921-110230 Reference 2: 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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- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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