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Real Estate Dispositions, Held for Sale, and Impairment Charges - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2018 USD ($) property | Dec. 31, 2017 USD ($) property | Dec. 31, 2016 USD ($) property
Schedule Of Real Estate Owned Held For Sale [Line Items] |  |  |
Number of real estate properties, held for sale | 1 |  |
Number of impaired assets, held and used | 0 |  |
Impairment charge | $ | $ 0 | $ 6,835,000 | $ 2,016,000
Gain (loss) on sale of real estate, net | $ | $ 2,763,000 | $ 3,993,000 | $ 242,000
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member] |  |  |
Schedule Of Real Estate Owned Held For Sale [Line Items] |  |  |
Number of impaired assets, held and used |  |  | 1
Number of impaired assets, sold | 1 | 2 | 5
Number of impaired assets, held for sale |  |  | 1
Held-for-sale |  |  |
Schedule Of Real Estate Owned Held For Sale [Line Items] |  |  |
Number of real estate properties, held for sale | 1 | 2 |
Number of impaired assets |  | 3 | 7

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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 Sale + References No definition available. + Details
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- Definition Number of Impaired Assets Sold + References No definition available. + Details
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- Definition Number of impaired Assets + References No definition available. + Details
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- Definition Schedule of real estate owned held for sale line items. + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + 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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228 + Details
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