CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	AOCI Attributable to Parent
Balance at Dec. 31, 2020	$ 4,904,611	$ 217,126	$ 75,850	$ 3,028,063	$ 1,407,723	$ 175,849
Balance (in shares) at Dec. 31, 2020			75,850,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of employee common stock options & related tax benefits	304		$ 13	291
Exercise of employee common stock options and related tax benefits (in shares)			13,000
Preferred dividends paid	(3,798)				(3,798)
Common dividends paid	(13,902)				(13,902)
Issuance of restricted common shares, net of forfeitures	0		$ 172	(172)
Issuance of restricted common shares, net of forfeitures (in shares)			172,000
Restricted shares withheld for taxes & related benefits	(2,456)		$ (34)	(2,422)
Restricted shares withheld for taxes (in shares)			(34,000)
Issuance of common stock pursuant to restricted stock unit agreement, net of shares withheld for taxes & related tax benefits	3,762		$ (86)	3,848
Issuance of common stock pursuant to restricted stock unit agreement, net of shares withheld for taxes and related tax benefit (in shares)			(86,000)
Stock-based compensation expense	5,399			5,399
Net income	125,428				125,428
Other comprehensive income (loss)	(52,301)					(52,301)
Balance at Mar. 31, 2021	4,959,523	217,126	$ 76,087	3,027,311	1,515,451	123,548
Balance (in shares) at Mar. 31, 2021			76,087,000
Balance at Dec. 31, 2020	4,904,611	217,126	$ 75,850	3,028,063	1,407,723	175,849
Balance (in shares) at Dec. 31, 2020			75,850,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	11,068
Net income	257,218
Other comprehensive income (loss)	(29,750)
Balance at Jun. 30, 2021	$ 5,101,231	217,126	$ 76,088	3,032,338	1,629,580	146,099
Balance (in shares) at Jun. 30, 2021			76,088,000
Common Stock, Dividends, Per Share, Cash Paid	$ 0.18
Preferred Stock, Dividends, Per Share, Cash Paid	$ 16.88
Balance at Mar. 31, 2021	$ 4,959,523	217,126	$ 76,087	3,027,311	1,515,451	123,548
Balance (in shares) at Mar. 31, 2021			76,087,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of employee common stock options & related tax benefits	100		$ 5	95
Exercise of employee common stock options and related tax benefits (in shares)			5,000
Preferred dividends paid	(3,798)				(3,798)
Common dividends paid	(13,863)				(13,863)
Issuance of restricted common shares, net of forfeitures	(739)		$ (8)	(731)
Issuance of restricted common shares, net of forfeitures (in shares)			(8,000)
Restricted shares withheld for taxes & related benefits	(2)		$ 1	(3)
Restricted shares withheld for taxes (in shares)			1,000
Issuance of common stock pursuant to restricted stock unit agreement, net of shares withheld for taxes & related tax benefits	5,669			(5,669)
Stock-based compensation expense	5,700
Net income	131,790				131,790
Other comprehensive income (loss)	22,551					22,551
Balance at Jun. 30, 2021	5,101,231	217,126	$ 76,088	3,032,338	1,629,580	146,099
Balance (in shares) at Jun. 30, 2021			76,088,000
Balance at Dec. 31, 2021	5,310,607	217,126	$ 76,143	3,045,802	1,864,350	107,186
Balance (in shares) at Dec. 31, 2021			76,143,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of employee common stock options & related tax benefits	130		$ 6	124
Exercise of employee common stock options and related tax benefits (in shares)			6,000
Preferred dividends paid	(3,798)				(3,798)
Common dividends paid	(16,976)				(16,976)
Issuance of restricted common shares, net of forfeitures	0		$ 158	(158)
Issuance of restricted common shares, net of forfeitures (in shares)			158,000
Restricted shares withheld for taxes & related benefits	(3,771)		$ (35)	(3,736)
Restricted shares withheld for taxes (in shares)			(35,000)
Issuance of common stock pursuant to restricted stock unit agreement, net of shares withheld for taxes & related tax benefits	5,461		$ (105)	5,566
Issuance of common stock pursuant to restricted stock unit agreement, net of shares withheld for taxes and related tax benefit (in shares)			(105,000)
Stock-based compensation expense	9,448			9,448
Net income	129,110				129,110
Other comprehensive income (loss)	(138,339)					(138,339)
Balance at Mar. 31, 2022	5,280,950	217,126	$ 76,377	3,045,914	1,972,686	(31,153)
Balance (in shares) at Mar. 31, 2022			76,377,000
Balance at Dec. 31, 2021	5,310,607	217,126	$ 76,143	3,045,802	1,864,350	107,186
Balance (in shares) at Dec. 31, 2021			76,143,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	20,208
Net income	274,237
Other comprehensive income (loss)	(238,636)
Balance at Jun. 30, 2022	$ 5,315,239	217,126	$ 76,385	3,056,228	2,096,950	(131,450)
Balance (in shares) at Jun. 30, 2022			76,385,000
Common Stock, Dividends, Per Share, Cash Paid	$ 0.22
Preferred Stock, Dividends, Per Share, Cash Paid	$ 16.88
Balance at Mar. 31, 2022	$ 5,280,950	217,126	$ 76,377	3,045,914	1,972,686	(31,153)
Balance (in shares) at Mar. 31, 2022			76,377,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of employee common stock options & related tax benefits	193		$ 8	185
Exercise of employee common stock options and related tax benefits (in shares)			8,000
Preferred dividends paid	(3,798)				(3,798)
Common dividends paid	(17,065)				(17,065)
Issuance of restricted common shares, net of forfeitures	0		$ 8	(8)
Issuance of restricted common shares, net of forfeitures (in shares)			8,000
Restricted shares withheld for taxes & related benefits	(631)		$ (8)	(623)
Restricted shares withheld for taxes (in shares)			(8,000)
Stock-based compensation expense	10,760			10,760
Net income	145,127				145,127
Other comprehensive income (loss)	(100,297)					(100,297)
Balance at Jun. 30, 2022	$ 5,315,239	$ 217,126	$ 76,385	$ 3,056,228	$ 2,096,950	$ (131,450)
Balance (in shares) at Jun. 30, 2022			76,385,000