Consolidated Statements Of Changes In Equity - USD ($) shares in Thousands, $ in Thousands	Total	Total Equity [Member]	Total Shareholders' Equity [Member]	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]	Redeemable Noncontrolling Interests [Member]
Balance at Dec. 31, 2017		$ 9,501,581	$ 9,504,148	$ 3,381,834	$ 3,776,743	$ 2,345,571	$ (2,567)
Balance, shares at Dec. 31, 2017				13,904
Balance, redeemable noncontrolling interests at Dec. 31, 2017								$ 166,269
Net income (loss)	$ (65,594)	(64,799)	(64,306)		(64,306)	0	(493)	(795)
Other comprehensive income (loss)	(110,491)	(110,533)	(110,533)		0	(110,533)	0	42
Comprehensive Income (Loss)	(176,085)	(175,332)	(174,839)				(493)	(753)
Issuance of common stock		2	2	$ 2	0	0	0	0
Issuance of common stock, shares				2
Repurchase of common stock		(12,289)	(12,289)	$ 0	(12,289)	0	0	0
Repurchase of common stock, shares				(11)
Restricted stock units expensed		7,212	7,212	$ 7,212	0	0	0	0
Restricted stock units expensed, shares				0
Adjustment of redeemable noncontrolling interests		5,051	5,051	$ 0	5,051	0	0	(5,051)
Adjustment of redeemable noncontrolling interests, shares				0
Purchase of noncontrolling interest		(5,391)	(5,391)	$ (5,391)	0	0	0	(39)
Purchase of noncontrolling interest, shares				0
Other		(9)	(8)	$ 11	(19)	0	(1)	(4,706)
Other, shares				0
Balance at Mar. 31, 2018		9,321,150	9,324,211	$ 3,383,668	5,927,739	12,804	(3,061)
Balance, shares at Mar. 31, 2018				13,895
Balance, redeemable noncontrolling interests at Mar. 31, 2018								155,720
Balance at Dec. 31, 2018	9,100,302	9,100,302	9,080,653	$ 3,392,993	5,782,310	(94,650)	19,649
Balance, shares at Dec. 31, 2018				13,888
Balance, redeemable noncontrolling interests at Dec. 31, 2018	174,062							174,062
Net income (loss)	577,513	577,185	576,427		576,427	0	758	328
Other comprehensive income (loss)	155,823	155,818	155,818		0	155,818	0	5
Comprehensive Income (Loss)	733,336	733,003	732,245				758	333
Issuance of common stock		0	0	$ 0	0	0	0	0
Issuance of common stock, shares				5
Repurchase of common stock		(37,649)	(37,649)	$ 0	(37,649)	0	0	0
Repurchase of common stock, shares				(37)
Restricted stock units expensed		6,848	6,848	$ 6,848	0	0	0	0
Restricted stock units expensed, shares				0
Adjustment of redeemable noncontrolling interests		18,361	18,361	$ 0	18,361	0	0	(18,361)
Adjustment of redeemable noncontrolling interests, shares				0
Purchase of noncontrolling interest		(3,736)	(3,736)	$ (3,736)	0	0	0	(5,025)
Purchase of noncontrolling interest, shares				0
Other		1,217	(740)	$ (165)	(575)	0	1,957	(3,007)
Other, shares				0
Balance at Mar. 31, 2019	9,818,346	$ 9,818,346	$ 9,795,982	$ 3,395,940	$ 6,338,874	$ 61,168	$ 22,364
Balance, shares at Mar. 31, 2019				13,856
Balance, redeemable noncontrolling interests at Mar. 31, 2019	$ 148,002							$ 148,002