Equity - Rollforward of Redeemable Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Redeemable Noncontrolling Interest, Equity, Carrying Amount
Balance - beginning of period	$ 14,944
Distributions	(17,030)	$ (14,713)	$ (19,719)
Redemption value adjustment	561	(8,873)	306
Net income	0	0	(142)
Change in other comprehensive income	0	0	(9)
Balance - end of period	965	14,944
Redeemable Noncontrolling Interest
Redeemable Noncontrolling Interest, Equity, Carrying Amount
Balance - beginning of period	14,944	6,071	7,436
Distributions	(13,418)	0	(926)
Redemption value adjustment	(561)	8,873	(306)
Net income	0	0	(142)
Change in other comprehensive income	0	0	9
Balance - end of period	$ 965	$ 14,944	$ 6,071