Consolidated Statements of Changes in Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjusted Balance	Cumulative Effect, Period of Adoption, Adjustment	Common Stock [Member]	Common Stock [Member] Cumulative Effect, Period of Adoption, Adjusted Balance	Capital Surplus [Member]	Capital Surplus [Member] Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment	Treasury Stock [Member]	Treasury Stock [Member] Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Other Comprehensive Income (Loss) [Member] Cumulative Effect, Period of Adoption, Adjusted Balance	Total Shareholders' Equity [Member]	Total Shareholders' Equity [Member] Cumulative Effect, Period of Adoption, Adjusted Balance	Total Shareholders' Equity [Member] Cumulative Effect, Period of Adoption, Adjustment	Non-Controlling Interests [Member]	Non-Controlling Interests [Member] Cumulative Effect, Period of Adoption, Adjusted Balance
Balance, beginning of period (in shares) at Dec. 31, 2018				75,711	75,711						3,589	3,589
Balance, beginning of period at Dec. 31, 2018	$ 4,443,045	$ 4,445,907	$ 2,862	$ 5	$ 5	$ 1,334,030	$ 1,334,030	$ 3,369,654	$ 3,372,516	$ 2,862	$ (198,995)	$ (198,995)	$ (72,585)	$ (72,585)	$ 4,432,109	$ 4,434,971	$ 2,862	$ 10,936	$ 10,936
Net income	248,045							248,175							248,175			(130)
Other comprehensive income (loss)	171,154												171,154		171,154
Repurchase of common stock (in shares)											955
Repurchase of common stock	(80,702)										$ (80,702)				(80,702)
Stock options exercised (in shares)				18
Stock options exercised	903					903									903
Non-vested shares awarded, net (in shares)				27
Non-vested shares awarded, net						0
Vesting of non-vested shares (in shares)											18
Vesting of non-vested shares	(1,428)										$ (1,428)				(1,428)
Share-based compensation	8,149					8,149									8,149
Cash dividends on common stock	(71,784)							(71,784)							(71,784)
Capital calls and distributions, net	(1,769)																	(1,769)
Balance, end of period (in shares) at Jun. 30, 2019				75,756							4,562
Balance, end of period at Jun. 30, 2019	4,718,475			$ 5		1,343,082		3,548,907			$ (281,125)		98,569		4,709,438			9,037
Balance, beginning of period (in shares) at Mar. 31, 2019				75,762							4,312
Balance, beginning of period at Mar. 31, 2019	4,531,709			$ 5		1,340,323		3,447,076			$ (261,000)		(3,531)		4,522,873			8,836
Net income	137,780							137,563							137,563			217
Other comprehensive income (loss)	102,100												102,100		102,100
Repurchase of common stock (in shares)											250
Repurchase of common stock	(20,125)										$ (20,125)				(20,125)
Stock options exercised (in shares)				0
Stock options exercised	24					24									24
Non-vested shares awarded, net (in shares)				(6)
Non-vested shares awarded, net						0
Vesting of non-vested shares (in shares)											0
Vesting of non-vested shares	0										$ 0				0
Share-based compensation	2,735					2,735									2,735
Cash dividends on common stock	(35,732)							(35,732)							(35,732)
Capital calls and distributions, net	(16)																	(16)
Balance, end of period (in shares) at Jun. 30, 2019				75,756							4,562
Balance, end of period at Jun. 30, 2019	4,718,475			$ 5		1,343,082		3,548,907			$ (281,125)		98,569		4,709,438			9,037
Balance, beginning of period (in shares) at Dec. 31, 2019				75,759	75,759						5,179	5,179
Balance, beginning of period at Dec. 31, 2019	4,863,919	$ 4,817,223	$ (46,696)	$ 5	$ 5	1,350,995	$ 1,350,995	3,729,778	$ 3,683,082	$ (46,696)	$ (329,906)	$ (329,906)	104,923	$ 104,923	4,855,795	$ 4,809,099	$ (46,696)	8,124	$ 8,124
Net income	126,270							126,772							126,772			(502)
Other comprehensive income (loss)	265,393												265,393		265,393
Repurchase of common stock (in shares)											442
Repurchase of common stock	(33,380)										$ (33,380)				(33,380)
Stock options exercised (in shares)				10
Stock options exercised	586					586									586
Non-vested shares awarded, net (in shares)				230
Non-vested shares awarded, net						0
Vesting of non-vested shares (in shares)											72
Vesting of non-vested shares	(5,608)										$ (5,608)				(5,608)
Share-based compensation	6,125					6,125									6,125
Cash dividends on common stock	(71,992)							(71,992)							(71,992)
Capital calls and distributions, net	(194)																	(194)
Balance, end of period (in shares) at Jun. 30, 2020				75,999							5,693
Balance, end of period at Jun. 30, 2020	5,104,423			$ 5		1,357,706		3,737,862			$ (368,894)		370,316		5,096,995			7,428
Balance, beginning of period (in shares) at Mar. 31, 2020				76,001							5,692
Balance, beginning of period at Mar. 31, 2020	5,034,160			$ 5		1,354,826		3,709,019			$ (368,894)		331,292		5,026,248			7,912
Net income	64,286							64,693							64,693			(407)
Other comprehensive income (loss)	39,024												39,024		39,024
Repurchase of common stock (in shares)											0
Repurchase of common stock	0										$ 0				0
Stock options exercised (in shares)				0
Stock options exercised	0					0									0
Non-vested shares awarded, net (in shares)				(2)
Non-vested shares awarded, net						0
Vesting of non-vested shares (in shares)											1
Vesting of non-vested shares	0										$ 0				0
Share-based compensation	2,880					2,880									2,880
Cash dividends on common stock	(35,850)							(35,850)							(35,850)
Capital calls and distributions, net	(77)																	(77)
Balance, end of period (in shares) at Jun. 30, 2020				75,999							5,693
Balance, end of period at Jun. 30, 2020	$ 5,104,423			$ 5		$ 1,357,706		$ 3,737,862			$ (368,894)		$ 370,316		$ 5,096,995			$ 7,428