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Real Estate Dispositions, Held for Sale and Impairment Charges - Components of Income from Real Estate and Related Assets Held for Sale (Detail) - USD ($) | 3 Months Ended
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Mar. 31, 2017 | Mar. 31, 2016
Real Estate Properties [Line Items] |  |
Operating expense | $ 17,708,000 | $ 13,257,000
Gain on sale of real estate, net | 5,906,000 | 0
Franklin, New Jersey |  |
Real Estate Properties [Line Items] |  |
Gain on sale of real estate, net | 5,900,000.0 |
Assets disposed of by sale |  |
Real Estate Properties [Line Items] |  |
Operating revenue | 87,000 | 247,000
Operating expense | 0 | 54,000
Other income (expense) | 5,781,000 | (93,000)
Income (loss) from real estate and related assets held for sale | 5,868,000 | 100,000
Gain on sale of real estate, net | 5,906,000 |
Assets held for sale |  |
Real Estate Properties [Line Items] |  |
Operating revenue | 51,000 | 59,000
Operating expense | 1,000 | 47,000
Other income (expense) | (28,000) | (36,000)
Income (loss) from real estate and related assets held for sale | $ 22,000 | $ (24,000)

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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=56944662&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=26872669&loc=d3e20235-122688 + Details
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