Property Dispositions and Discontinued Operations - Property Dispositions Included in Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disposal Group, Including Discontinued Operation, Income Statement Disclosures
Income (loss) from continuing operations from properties sold or classified as held for sale, net of income taxes	$ 0	$ 0	$ 33,497
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Disposal Group, Including Discontinued Operation, Income Statement Disclosures
Revenues	96,625	107,494	98,959
Expenses	(44,681)	(62,606)	(81,260)
Gain on sale of real estate	71,122	6,487	1,334
Impairment charges	(50,769)	(4,071)	(22,491)
Loss on extinguishment of debt	(4,498)	(3,156)	(167)
Benefit from (provision for) income taxes	12,493	(7,187)	(3,973)
Income (loss) from continuing operations from properties sold or classified as held for sale, net of income taxes	$ 80,292	$ 36,961	$ (7,598)

Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
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-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

+ References

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