CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	Class C non-voting common stock	Series G	Series E	5.250% Non-Cumulative Preferred Stock, Series F	Series A	Preferred Stock	Preferred Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Preferred Stock Series G	Preferred Stock Series E	Preferred Stock 5.250% Non-Cumulative Preferred Stock, Series F	Preferred Stock Series A	Common Stock	Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock Class C non-voting common stock	Additional Paid-in Capital	Additional Paid-in Capital Cumulative Effect, Period of Adoption, Adjusted Balance	Additional Paid-in Capital Class C non-voting common stock	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings Class C non-voting common stock
Beginning balance ( in shares) at Dec. 31, 2019									9,400	9,400					10,712	10,712
Beginning balance at Dec. 31, 2019	$ 799,276	$ (2,099)	$ 797,177						$ 228,374	$ 228,374					$ 10,712	$ 10,712		$ 119,304	$ 119,304		$ (16,161)	$ (16,161)	$ 457,047	$ (2,099)	$ 454,948
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	12,830																						12,830
Other comprehensive (loss)/income net of tax	(105,276)																				(105,276)
Cash dividends, preferred stock	(3,431)																						(3,431)
Cash dividends, common stock	(8,571)																						(8,571)
Issuance of common stock (in shares)																	15
Issuance of common stock				$ 34													$ 15			$ 19
Repurchase of Class C Common Stock (in shares)																	(4)
Repurchase of Class C Common Stock	(235)																$ (4)									$ (231)
Stock-based compensation cost	1,293																	1,293
Other stock-based award activity	(204)																	(204)
Ending balance (in shares) at Mar. 31, 2020									9,400						10,723
Ending balance at Mar. 31, 2020	693,617								$ 228,374						$ 10,723			120,412			(121,437)		455,545
Beginning balance ( in shares) at Dec. 31, 2019									9,400	9,400					10,712	10,712
Beginning balance at Dec. 31, 2019	799,276	$ (2,099)	$ 797,177						$ 228,374	$ 228,374					$ 10,712	$ 10,712		119,304	$ 119,304		(16,161)	$ (16,161)	457,047	$ (2,099)	$ 454,948
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	73,948
Other comprehensive (loss)/income net of tax	(37,676)
Loss on retirement of preferred stock	(1,667)
Ending balance (in shares) at Sep. 30, 2020									14,980						10,736
Ending balance at Sep. 30, 2020	930,345								$ 363,204						$ 10,736			121,525			(53,837)		488,717
Beginning balance ( in shares) at Mar. 31, 2020									9,400						10,723
Beginning balance at Mar. 31, 2020	693,617								$ 228,374						$ 10,723			120,412			(121,437)		455,545
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	35,626																						35,626
Other comprehensive (loss)/income net of tax	29,940																				29,940
Cash dividends, preferred stock	(3,939)																						(3,939)
Cash dividends, common stock	(8,585)																						(8,585)
Issuance of common stock (in shares)												3,180					10
Issuance of common stock				27		$ 77,003						$ 77,003					$ 10			17
Stock-based compensation cost	719																	719
Other stock-based award activity	(292)																	(292)
Ending balance (in shares) at Jun. 30, 2020									12,580						10,733
Ending balance at Jun. 30, 2020	824,116								$ 305,377						$ 10,733			120,856			(91,497)		478,647
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	25,492																						25,492
Other comprehensive (loss)/income net of tax	37,660																				37,660
Cash dividends, preferred stock	(5,166)																						(5,166)
Cash dividends, common stock	(8,589)																						(8,589)
Issuance of common stock (in shares)													4,800				3
Issuance of common stock				11			$ 116,160						$ 116,160				$ 3			8
Redemption of stock (in shares)														(2,400)
Redemption of stock								$ (58,333)						$ (58,333)
Loss on retirement of preferred stock	(1,667)																						(1,667)
Stock-based compensation cost	753																	753
Other stock-based award activity	(92)																	(92)
Ending balance (in shares) at Sep. 30, 2020									14,980						10,736
Ending balance at Sep. 30, 2020	930,345								$ 363,204						$ 10,736			121,525			(53,837)		488,717
Beginning balance ( in shares) at Dec. 31, 2020									14,980						10,737
Beginning balance at Dec. 31, 2020	992,477								$ 363,204						$ 10,737			122,899			(13,923)		509,560
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	33,227																						33,227
Other comprehensive (loss)/income net of tax	65,667																				65,667
Cash dividends, preferred stock	(5,269)																						(5,269)
Cash dividends, common stock	(9,450)																						(9,450)
Issuance of common stock (in shares)																	21
Issuance of common stock				33													$ 21			12
Stock-based compensation cost	1,665																	1,665
Other stock-based award activity	(858)																	(858)
Ending balance (in shares) at Mar. 31, 2021									14,980						10,758
Ending balance at Mar. 31, 2021	1,077,492								$ 363,204						$ 10,758			123,718			51,744		528,068
Beginning balance ( in shares) at Dec. 31, 2020									14,980						10,737
Beginning balance at Dec. 31, 2020	992,477								$ 363,204						$ 10,737			122,899			(13,923)		509,560
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	95,576
Other comprehensive (loss)/income net of tax	32,129
Loss on retirement of preferred stock	0
Ending balance (in shares) at Sep. 30, 2021									19,980						10,766
Ending balance at Sep. 30, 2021	1,197,298								$ 484,531						$ 10,766			124,942			18,206		558,853
Beginning balance ( in shares) at Mar. 31, 2021									14,980						10,758
Beginning balance at Mar. 31, 2021	1,077,492								$ 363,204						$ 10,758			123,718			51,744		528,068
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	31,286																						31,286
Other comprehensive (loss)/income net of tax	(35,011)																				(35,011)
Cash dividends, preferred stock	(5,842)																						(5,842)
Cash dividends, common stock	(9,474)																						(9,474)
Issuance of common stock (in shares)											5,000						7
Issuance of common stock				20	$ 121,327						$ 121,327						$ 7			13
Stock-based compensation cost	891																	891
Other stock-based award activity	(474)																	(474)
Ending balance (in shares) at Jun. 30, 2021									19,980						10,765
Ending balance at Jun. 30, 2021	1,180,215								$ 484,531						$ 10,765			124,148			16,733		544,038
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	31,063																						31,063
Other comprehensive (loss)/income net of tax	1,473																				1,473
Cash dividends, preferred stock	(6,774)																						(6,774)
Cash dividends, common stock	(9,474)																						(9,474)
Issuance of common stock (in shares)																	1
Issuance of common stock				$ 46													$ 1			$ 45
Loss on retirement of preferred stock	0
Stock-based compensation cost	749																	749
Ending balance (in shares) at Sep. 30, 2021									19,980						10,766
Ending balance at Sep. 30, 2021	$ 1,197,298								$ 484,531						$ 10,766			$ 124,942			$ 18,206		$ 558,853