CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands		Total	Impact from Adoption	Preferred Stock	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Retained Earnings Impact from Adoption
Beginning balance at Dec. 31, 2019		$ 4,941,690	$ (35,721)	$ 537,145	$ 166,801	$ 3,819,336	$ (715,560)	$ 65,641	$ 1,068,327	$ (35,721)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		131,712							131,712
Other comprehensive income (loss)		137,329						137,329
Cash dividends declared on common stock		(97,210)							(97,210)
Cash dividends declared on preferred stock	[1]	(16,581)							(16,581)
Repurchases of common stock including costs to repurchase		(16,246)					(16,246)
Restricted share unit vesting and taxes paid related to net share settlement		(7,404)			379	(7,783)
Stock options exercised, net		6,479			226	6,253
Share-based compensation expense		8,920				8,920
Ending balance at Jun. 30, 2020		5,052,968		537,145	167,406	3,826,726	(731,806)	202,970	1,050,527
Beginning balance at Mar. 31, 2020		5,065,205		537,145	167,360	3,821,357	(731,806)	256,911	1,014,238
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		93,192							93,192
Other comprehensive income (loss)		(53,941)						(53,941)
Cash dividends declared on common stock		(48,612)							(48,612)
Cash dividends declared on preferred stock	[2]	(8,291)							(8,291)
Restricted share unit vesting and taxes paid related to net share settlement		(147)			34	(181)
Stock options exercised, net		212			12	200
Share-based compensation expense		5,350				5,350
Ending balance at Jun. 30, 2020		5,052,968		537,145	167,406	3,826,726	(731,806)	202,970	1,050,527
Beginning balance at Dec. 31, 2020		5,161,334		537,145	168,133	3,851,208	(731,806)	158,635	1,178,019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		373,292							373,292
Other comprehensive income (loss)		(112,909)						(112,909)
Cash dividends declared on common stock		(97,744)							(97,744)
Cash dividends declared on preferred stock	[1]	(16,581)							(16,581)
Repurchases of common stock including costs to repurchase		(92,507)					(92,507)
Restricted share unit vesting and taxes paid related to net share settlement		(6,579)			306	(6,885)
Stock options exercised, net		14,879			669	14,210
Warrants exercised with net settlement and common stock reissued		0				(113)	116		(3)
Share-based compensation expense		14,529				14,529
Ending balance at Jun. 30, 2021		5,237,714		537,145	169,108	3,872,949	(824,197)	45,726	1,436,983
Beginning balance at Mar. 31, 2021		5,161,717		537,145	168,978	3,864,281	(731,690)	15,278	1,307,725
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		186,200							186,200
Other comprehensive income (loss)		30,448						30,448
Cash dividends declared on common stock		(48,651)							(48,651)
Cash dividends declared on preferred stock	[2]	(8,291)							(8,291)
Repurchases of common stock including costs to repurchase		(92,507)					(92,507)
Restricted share unit vesting and taxes paid related to net share settlement		(394)			35	(429)
Stock options exercised, net		2,327			95	2,232
Share-based compensation expense		6,865				6,865
Ending balance at Jun. 30, 2021		$ 5,237,714		$ 537,145	$ 169,108	$ 3,872,949	$ (824,197)	$ 45,726	$ 1,436,983

[1] For the six months ended June 30, 2021 and 2020, dividends per share were $0.78 and $0.74 for Series D and Series E Preferred Stock, respectively. See accompanying notes to unaudited interim consolidated financial statements.

[2] For the three months ended June 30, 2021 and 2020, dividends per share were $0.39 and $0.37 for Series D and Series E Preferred Stock, respectively.