CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Total	Total Restricted Stock Units (RSUs)	Total Stock appreciation rights	Non-controlling interests subject to put provisions	Common stock	Common stock Restricted Stock Units (RSUs)	Common stock Stock appreciation rights	Additional paid-in capital	Additional paid-in capital Restricted Stock Units (RSUs)	Additional paid-in capital Stock appreciation rights	Retained earnings	Treasury stock	Accumulated other comprehensive income (loss)	Non-controlling interests not subject to put provisions
Temporary equity, beginning balance at Dec. 31, 2016					$ 973,258
Increase (Decrease) in Temporary Equity [Roll Forward]
Net income					103,641
Distributions					(128,853)
Contributions					52,911
Acquisitions and divestitures					43,799
Partial purchases					(397)
Fair value remeasurements					(32,999)
Temporary equity, ending balance at Dec. 31, 2017					1,011,360
Beginning balance (in shares) at Dec. 31, 2016						(194,554,000)							0
Beginning balance at Dec. 31, 2016		$ 4,648,047				$ 195			$ 1,027,182			$ 3,710,313	$ 0	$ (89,643)	$ 201,694
Comprehensive income:
Net income	$ 663,618	663,618										663,618			63,296
Other comprehensive income	$ 102,876	102,878												102,878	(2)
Stock purchase shares issued (in shares)						360,000
Stock purchase shares issued		22,131							22,131
Stock-settled share based payment awards, shares issued (in shares)							117,000	398,000
Stock-settled share based payment awards			$ (101)	$ 0						$ (101)	$ 0
Stock-settled stock-based compensation expense		34,981							34,981
Changes in noncontrolling interest from:
Distributions															(82,614)
Contributions															21,641
Acquisitions and divestitures		(823)							(823)
Acquisitions and divestitures, noncontrolling interest															(5,770)
Partial purchases		(2,752)							(2,752)						(2,208)
Fair value remeasurements		32,999							32,999
Purchase of treasury stock (in shares)	(12,967,000)												(12,967,000)
Purchase of treasury stock	$ (810,949)	(810,949)											$ (810,949)
Retirement of treasury stock (in shares)						(12,967,000)							12,967,000
Retirement of treasury stock						$ (13)			(70,718)			(740,218)	$ 810,949
Ending balance at Dec. 31, 2017		4,690,029				$ 182			1,042,899			3,633,713	$ 0	13,235	196,037
Ending balance (in shares) at Dec. 31, 2017						(182,462,000)							0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption		0										8,368		(8,368)
Net income					105,531
Distributions					(119,173)
Contributions					32,918
Acquisitions and divestitures					79,078
Partial purchases					(8,546)
Fair value remeasurements					23,473
Temporary equity, ending balance at Dec. 31, 2018					1,124,641
Comprehensive income:
Net income	159,394	159,394										159,394			68,115
Other comprehensive income	$ (39,791)	(39,791)												(39,791)
Stock purchase shares issued (in shares)						398,000
Stock purchase shares issued		17,398							17,398
Stock-settled share based payment awards, shares issued (in shares)							158,000	213,000
Stock-settled share based payment awards			(448)	(4,886)				$ (1)		(448)	(4,887)
Stock-settled stock-based compensation expense		73,081							73,081
Changes in noncontrolling interest from:
Distributions															(77,268)
Contributions															19,393
Acquisitions and divestitures		3,546							3,546
Acquisitions and divestitures, noncontrolling interest															318
Partial purchases		(17,897)							(17,897)						(1,639)
Fair value remeasurements		(23,473)							(23,473)
Purchase of treasury stock (in shares)	(16,844,000)												(16,844,000)
Purchase of treasury stock	$ (1,153,511)	(1,153,511)											$ (1,153,511)
Retirement of treasury stock (in shares)						(16,844,000)							16,844,000
Retirement of treasury stock		0				$ (17)			(95,213)			(1,058,281)	$ 1,153,511
Ending balance at Dec. 31, 2018	$ 3,908,398	3,703,442				$ 166			995,006			2,743,194	$ 0	(34,924)	204,956
Ending balance (in shares) at Dec. 31, 2018	(166,387,307)					(166,387,000)							0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption		39,876			(38)							39,876			(6)
Net income					143,413
Distributions					(155,011)
Contributions					35,572
Acquisitions and divestitures					(6,332)
Partial purchases					(11,394)
Fair value remeasurements					49,525
Temporary equity, ending balance at Dec. 31, 2019					$ 1,180,376
Comprehensive income:
Net income	$ 810,981	810,981										810,981			66,900
Other comprehensive income	$ (12,574)	(12,574)												(12,574)
Stock purchase shares issued (in shares)						315,000
Stock purchase shares issued		16,570				$ 1			16,569
Stock-settled share based payment awards, shares issued (in shares)							160,000	1,000
Stock-settled share based payment awards			$ (3,246)	$ (44)						$ (3,246)	$ (44)
Stock-settled stock-based compensation expense		67,549							67,549
Changes in noncontrolling interest from:
Distributions															(78,112)
Contributions															21,745
Acquisitions and divestitures, noncontrolling interest															(10,170)
Partial purchases		(37,145)							(37,145)						(19,480)
Fair value remeasurements		(49,525)							(49,525)
Purchase of treasury stock (in shares)	(41,020,000)												(41,020,000)
Purchase of treasury stock	$ (2,402,475)	(2,402,475)											$ (2,402,475)
Retirement of treasury stock (in shares)						(41,020,000)							41,020,000
Retirement of treasury stock		0				$ (41)			(240,121)			(2,162,313)	$ 2,402,475
Ending balance at Dec. 31, 2019	$ 2,319,242	$ 2,133,409				$ 126			$ 749,043			$ 1,431,738	$ 0	$ (47,498)	$ 185,833
Ending balance (in shares) at Dec. 31, 2019	(125,842,853)					(125,843,000)							0