Debt - Mortgage Notes Payable Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) property	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 30, 2016 USD ($) property	Mar. 06, 2015 USD ($) property
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt, net	$ (771)	$ 4,812	$ (21,869)
Notes assumed	55,000	425,021	461,111
Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt, net	300	(100)
Mortgage notes in connection with default from non-recourse loan			$ 53,800	$ 11,600	$ 38,100
Gain (loss) on forgiveness of debt	$ (3,400)	$ 4,900
Number of non-recourse loan secured properties | property	2			16	2
Mortgage Notes Payable [Member] | Foreclosure [Member]
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt, net	$ 19,100
Mortgage Notes Payable [Member] | 2016 Consolidated Property Dispositions [Member]
Debt Instrument [Line Items]
Notes assumed	$ 55,000