Property Dispositions - Results of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Disposal Group, Including Discontinued Operation, Income Statement Disclosures
Revenues	$ 123,005	$ 107,226
Expenses	(59,615)	(56,205)
Equity in earnings of equity method investments in real estate	1,985	2,172
Loss on extinguishment of debt	(1,614)	(2,499)
Provision for income taxes	(621)	(1,903)
Gain on sale of real estate, net of tax	1,739	25,398
Income before gain on sale of real estate, net of tax	45,407	30,219
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Disposal Group, Including Discontinued Operation, Income Statement Disclosures
Revenues	6,677	11,566
Expenses	(4,045)	(8,631)
Equity in earnings of equity method investments in real estate	(688)	(1,172)
Loss on extinguishment of debt	(1,320)	(2,499)
Provision for income taxes	(10)	(5)
Gain on sale of real estate, net of tax	1,634	25,398
Income before gain on sale of real estate, net of tax	$ 2,248	$ 24,657