Property Dispositions - Results of Operations (Details) - Assets held for sale - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Mar. 13, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Disposal Group, Including Discontinued Operation, Income Statement Disclosures
Revenues		$ 0	$ 10,680	$ 7,245	$ 32,611
Expenses		0	(7,243)	(4,258)	(23,041)
Gain on sale of real estate, net of tax	$ 1,600	0	82,287	2,805	132,703
Impairment charges		0	(29,183)	0	(29,183)
Loss on extinguishment of debt		0	(8,218)	(1,364)	(15,807)
Provision for income taxes		0	(1)	(2)	(24)
Equity in earnings of equity method investments in real estate		0	1,154	(688)	(2,336)
Income before gain on sale of real estate, net of tax		$ 0	$ 49,476	$ 3,738	$ 94,923