CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Non-controlling Interest [Member]	Redeemable Noncontrolling Interests (Temporary Equity) [Member]
Total Equity Balance at Dec. 31, 2012	$ 2,128,051	$ 1,489	$ 1,405,699	$ 452,598	$ (38,862)	$ 307,127
Comprehensive income (loss)	698,288			505,070	26,333	166,885
Redeemable non-controlling interest fair value adjustments	7,933			7,933			$ (7,933)
Dividends paid to non-controlling interests	(154,123)					(154,123)	(6,370)
Dividends: declared and paid	(88,400)			(88,400)
Repurchases of class A common shares	(253,203)	(39)	(38,537)	(214,627)
Share-based compensation expense	36,845		36,845
Exercise of employee share options	42,976	9	42,967
Other share-based compensation, net	(4,364)	3	(4,367)
Tax benefits of compensation plans	4,889		4,889
Total Equity Balance at Dec. 31, 2013	2,418,892	1,462	1,447,496	662,574	(12,529)	319,889
Redeemable Non-controlling Interests (Temporary Equity) Balance at Dec. 31, 2012	136,500
Comprehensive income (loss)	10,803
Redeemable Non-controlling Interests (Temporary Equity) Balance at Dec. 31, 2013	133,000
Comprehensive income (loss)	671,461			545,275	(45,362)	171,548
Redeemable non-controlling interest fair value adjustments	18,865			18,865			(18,865)
Dividends paid to non-controlling interests	(189,297)					(189,297)	(27,563)
Dividends: declared and paid	(112,943)			(112,943)
Repurchases of class A common shares	(1,198,962)	(154)	(165,031)	(1,033,777)
Share-based compensation expense	35,474		35,474
Exercise of employee share options	39,605	10	39,595
Other share-based compensation, net	(10,847)	3	(10,850)
Tax benefits of compensation plans	12,339		12,339
Total Equity Balance at Dec. 31, 2014	1,684,587	1,321	1,359,023	79,994	(57,891)	302,140
Comprehensive income (loss)	9,679
Redeemable Non-controlling Interests (Temporary Equity) Balance at Dec. 31, 2014	96,251
Comprehensive income (loss)	705,071			606,828	(72,342)	170,585
Redeemable non-controlling interest fair value adjustments	(17,794)			(17,794)			17,794
Dividends paid to non-controlling interests	(164,157)					(164,157)	(12,985)
Dividends: declared and paid	(118,857)			(118,857)
Repurchases of class A common shares	(288,502)	(40)	(43,677)	(244,785)
Share-based compensation expense	29,568		29,568
Exercise of employee share options	9,209	2	9,207
Other share-based compensation, net	(7,856)	4	(7,860)
Tax benefits of compensation plans	1,230		1,230
Total Equity Balance at Dec. 31, 2015	1,837,176	$ 1,287	$ 1,347,491	$ 305,386	$ (130,233)	313,245
Purchase of non-controlling interests	(853,853)					(853,853)
Addition to non-controlling interests	858,530					$ 858,530
Comprehensive income (loss)	(2,760)
Dividends declared and paid: $0.60 per share	700						$ 700
Redeemable Non-controlling Interests (Temporary Equity) Balance at Dec. 31, 2015	$ 99,000