Consolidated Statements of Changes in Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total Shareholders' Equity [Member]	Non-Controlling Interests [Member]
Balance, beginning of period (in shares) at Dec. 31, 2015		74,530			8,636
Balance, beginning of period at Dec. 31, 2015	$ 3,267,639	$ 4	$ 982,009	$ 2,704,121	$ (477,165)	$ 21,587	$ 3,230,556	$ 37,083
Net income (loss)	107,260			108,365			108,365	(1,105)
Other comprehensive income	96,045					96,045	96,045
Repurchase of common stock (in shares)					305
Repurchase of common stock	(17,770)				$ (17,770)		(17,770)
Stock options exercised (in shares)		39
Stock options exercised	2,016		2,016				2,016
Non-vested shares awarded, net (in shares)		248
Vesting of non-vested shares (in shares)					10
Vesting of non-vested shares	(260)				$ 260		(260)
Tax effect from equity compensation, net	351		351				351
Share-based compensation	5,730		5,730				5,730
Cash dividends on common stock	(56,720)			(56,720)			(56,720)
Capital calls and distributions, net	(2,073)							(2,073)
Balance, end of period (in shares) at Jun. 30, 2016		74,817			8,951
Balance, end of period at Jun. 30, 2016	3,402,738	$ 4	990,106	2,755,766	$ (494,675)	117,632	3,368,833	33,905
Balance, beginning of period (in shares) at Dec. 31, 2016		74,993			9,656
Balance, beginning of period at Dec. 31, 2016	3,306,357	$ 4	1,006,535	2,823,334	$ (544,052)	(10,967)	3,274,854	31,503
Net income (loss)	177,530			176,503			176,503	1,027
Other comprehensive income	18,931					18,931	18,931
Stock options exercised (in shares)		41
Stock options exercised	1,977		1,977				1,977
Non-vested shares awarded, net (in shares)		55
Vesting of non-vested shares (in shares)					17
Vesting of non-vested shares	(1,389)				$ (1,389)		(1,389)
Share-based compensation	8,983		8,983				8,983
Cash dividends on common stock	(57,390)			(57,390)			(57,390)
Capital calls and distributions, net	(5,454)							(5,454)
Balance, end of period (in shares) at Jun. 30, 2017		75,089			9,673
Balance, end of period at Jun. 30, 2017	$ 3,449,545	$ 4	$ 1,017,495	$ 2,942,447	$ (545,441)	$ 7,964	$ 3,422,469	$ 27,076