CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Series E Preferred Stock	Impact of ASU 2016-13 adoption	Adjusted balance at January 1, 2020	Preferred Stock	Preferred Stock Series E Preferred Stock	Preferred Stock Adjusted balance at January 1, 2020	Common Stock	Common Stock Adjusted balance at January 1, 2020	Capital Surplus	Capital Surplus Adjusted balance at January 1, 2020	Retained Earnings	Retained Earnings Impact of ASU 2016-13 adoption	Retained Earnings Adjusted balance at January 1, 2020	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Adjusted balance at January 1, 2020
Balance at beginning of period at Dec. 31, 2019	$ 1,578,137		$ (14,891)	$ 1,563,246	$ 0		$ 0	$ 36,704	$ 36,704	$ 839,857	$ 839,857	$ 702,502	$ (14,891)	$ 687,611	$ (926)	$ (926)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	154,481											98,129			56,352
Cash dividends declared:
Preferred	(2,437)											(2,437)
Common	(22,092)											(22,092)
Issuance of shares of Series E preferred Stock		$ 110,705				$ 110,705
Issuance of shares of common stock	2,150							181		1,969
Stock based compensation	5,551									5,551
Balance at end of period at Sep. 30, 2020	1,811,604				110,705			36,885		847,377		761,211			55,426
Balance at beginning of period at Jun. 30, 2020	1,747,377				110,705			36,845		844,202		723,067			32,558
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	70,826											47,958			22,868
Cash dividends declared:
Preferred	(2,437)											(2,437)
Common	(7,377)											(7,377)
Issuance of shares of common stock	1,222							40		1,182
Stock based compensation	1,993									1,993
Balance at end of period at Sep. 30, 2020	1,811,604				110,705			36,885		847,377		761,211			55,426
Balance at beginning of period at Dec. 31, 2020	2,079,231				110,705			42,094		1,062,083		791,630			72,719
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	121,174											170,343			(49,169)
Cash dividends declared:
Preferred	(6,038)											(6,038)
Common	(29,101)											(29,101)
Issuance of shares of common stock	254							156		98
Stock based compensation	6,732									6,732
Balance at end of period at Sep. 30, 2021	2,172,252				110,705			42,250		1,068,913		926,834			23,550
Balance at beginning of period at Jun. 30, 2021	2,159,786				110,705			42,245		1,066,765		883,484			56,587
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	22,887											55,924			(33,037)
Cash dividends declared:
Preferred	(2,013)											(2,013)
Common	(10,561)											(10,561)
Issuance of shares of common stock	197							5		192
Stock based compensation	1,956									1,956
Balance at end of period at Sep. 30, 2021	$ 2,172,252				$ 110,705			$ 42,250		$ 1,068,913		$ 926,834			$ 23,550