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 E	Series G	Preferred Stock	Preferred Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Preferred Stock Series E	Preferred Stock Series G	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)	48,456
Other comprehensive (loss)/income net of tax	(75,336)
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
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
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)	64,513
Other comprehensive (loss)/income net of tax	30,656
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
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