Condensed Consolidated Statements of Equity - USD ($) $ in Thousands	Common Stock [Member] Deferred Compensation Plan [Member]	Common Stock [Member] Performance Shares [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]	Total
Beginning Balances at Dec. 31, 2016			$ 4,174,808	$ 102,220	$ (43,001)		$ 1,413,488	$ 7,362	$ 5,654,877
Beginning Balances, shares at Dec. 31, 2016			262,803,383
Beginning Balance, treasury shares at Dec. 31, 2016						337,397
Sale of common shares held in trust			$ 7,735						7,735
Sale of common shares held in trust, shares			125,744			(125,744)
Vesting of restricted share units (shares)	36,619	122,786	534,881
Tax withholdings related to net share settlements of equity-based compensation				(13,621)					(13,621)
Tax withholdings related to net share settlements of equity-based compensation, shares			(247,927)
Equity-based compensation				13,880					13,880
Exercise of stock options and warrants			$ 1,946						$ 1,946
Exercise of stock options and warrants, shares			49,954
Repurchase of common shares (shares)									0
Cash dividends on common shares							(63,463)		$ (63,463)
Amounts reclassified into earnings, net of taxes					2,575				2,575
Changes in fair value of cash flow hedges, net of taxes					(4,093)				(4,093)
Foreign currency translation adjustment					70,627				70,627
Net income							138,530	377	138,907
Ending Balances at Jun. 30, 2017			$ 4,184,489	103,863	26,108		1,487,171	7,739	5,809,370
Ending Balances, shares at Jun. 30, 2017			263,425,440
Ending Balance, treasury shares at Jun. 30, 2017						211,653
Cumulative effect adjustment from adoption of new accounting pronouncement				1,384			(1,384)
Beginning Balances at Dec. 31, 2017			$ 4,187,568	115,743	108,413		1,856,946	5,400	$ 6,274,070
Beginning Balances, shares at Dec. 31, 2017			263,494,670						263,494,670
Beginning Balance, treasury shares at Dec. 31, 2017						166,133			166,133
Sale of common shares held in trust			$ 2,146						$ 2,146
Sale of common shares held in trust, shares			29,487			(29,487)
Vesting of restricted share units (shares)	4,425	154,181	468,423
Tax withholdings related to net share settlements of equity-based compensation				(14,589)					(14,589)
Tax withholdings related to net share settlements of equity-based compensation, shares			(212,257)
Equity-based compensation				16,959					$ 16,959
Exercise of stock options and warrants, shares			17,571
Repurchase of common shares (shares)			(594,474)						(594,474)
Repurchase of common shares			$ (42,040)						$ (42,040)
Cash dividends on common shares							(73,584)		(73,584)
Amounts reclassified into earnings, net of taxes					(3,507)				(3,507)
Changes in fair value of cash flow hedges, net of taxes					13,004				13,004
Foreign currency translation adjustment					(102,804)				(102,804)
Distributions to noncontrolling interests								(103)	(103)
Net income							263,551	295	263,846
Ending Balances at Jun. 30, 2018			$ 4,147,674	$ 118,113	$ 15,106		2,060,156	$ 5,592	$ 6,346,641
Ending Balances, shares at Jun. 30, 2018			263,362,026						263,362,026
Ending Balance, treasury shares at Jun. 30, 2018						136,646			136,646
Cumulative effect adjustment from adoption of new accounting pronouncement							$ 13,243		$ 13,243