Redeemable Non-Controlling Interests (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance, beginning	$ 844,422	$ 833,241	$ 780,488	$ 616,232	$ 607,474	$ 640,818
Net income attributable to redeemable non-controlling interests	6,096	11,507	7,700	9,244	10,909	5,743
Issuance and exchange of redeemable non-controlling interests			0			163,659
Distributions to and purchases of redeemable non-controlling interests	(1,721)	(395)	(2,771)	(763)	(11,112)	(203,972)
Redemption adjustment on redeemable non-controlling interests	104,553	(270)	47,470	154,514	8,500	1,051
Other	347	339	354	347	461	175
Balance, ending	$ 953,697	$ 844,422	$ 833,241	$ 779,574	$ 616,232	$ 607,474