Condensed Consolidated Statement of Shareholders' Equity - USD ($) $ in Thousands	Common stock		Preferred stock 8% Preferred Stock	Preferred stock 7% Series A Preferred Stock	Preferred stock 6% Series B Preferred Stock	Preferred stock 6% Series C Preferred Stock Public Offering	Preferred stock 6% Series C Preferred Stock Private Placement	Preferred stock 6% Series C Preferred Stock	Preferred stock 8.25% Series D Preferred Stock Public Offering	Preferred stock 8.25% Series D Preferred Stock	Retained Earnings Impact from adoption of ASU	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Total
Balance at beginning of the period at Dec. 31, 2020	$ 135,857	[1]	$ 41,581	$ 50,221	$ 120,844							$ 461,744	$ 374
Balance at beginning of the period (in shares) at Dec. 31, 2020	43,120,625	[1]	41,625	2,081,800	125,000
Condensed Consolidated Statements of Shareholders' Equity
Net income												171,903		$ 171,903
Issuance of shares, net of offering expenses						$ 144,926	$ 46,158
Issuance of shares, net of offering expenses (in shares)						150,000	46,181
Dividends on 8% preferred stock, annually												(833)
Final dividend for redemption of 8% preferred stock												(139)
Dividends on 7% preferred stock, annually												(2,732)
Dividends on 6% Series B preferred stock, annually												(5,625)
Dividends on 6% Series C preferred stock, annually												(5,816)
Dividends on common stock, annually												(7,771)
Deconsolidation of entities												(419)
Other comprehensive income (loss)													(112)	$ (112)
Redemption of 8% preferred stock			$ (41,581)									(45)
Redemption of 8% preferred stock (in shares)			(41,625)
Repurchase of common stock (in shares)														0
Distribution to employee stock ownership plan	$ 537
Distribution to employee stock ownership plan (in shares)	29,149
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations	$ 806
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations (in shares)	28,287
Balance at end of the period at Sep. 30, 2021	$ 137,200			$ 50,221	$ 120,844			$ 191,084				610,267	262	$ 1,109,878
Balance at end of the period (in shares) at Sep. 30, 2021	43,178,061			2,081,800	125,000			196,181
Balance at beginning of the period at Jun. 30, 2021	$ 136,836	[1]		$ 50,221	$ 120,844			$ 191,084				560,083	(4)
Balance at beginning of the period (in shares) at Jun. 30, 2021	43,175,398	[1]		2,081,800	125,000			196,181
Condensed Consolidated Statements of Shareholders' Equity
Net income												58,503		58,503
Dividends on 7% preferred stock, annually												(911)
Dividends on 6% Series B preferred stock, annually												(1,875)
Dividends on 6% Series C preferred stock, annually												(2,943)
Dividends on common stock, annually												(2,590)
Other comprehensive income (loss)													266	$ 266
Repurchase of common stock (in shares)														0
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations	$ 364
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations (in shares)	2,663
Balance at end of the period at Sep. 30, 2021	$ 137,200			$ 50,221	$ 120,844			$ 191,084				610,267	262	$ 1,109,878
Balance at end of the period (in shares) at Sep. 30, 2021	43,178,061			2,081,800	125,000			196,181
Balance at beginning of the period (ASU 2016-13) at Dec. 31, 2021											$ (3,648)
Balance at beginning of the period (ASU 2016-02) at Dec. 31, 2021											$ (110)
Balance at beginning of the period at Dec. 31, 2021	$ 137,565	[1]		$ 50,221	$ 120,844			$ 191,084				657,149	(1,454)	1,155,409
Balance at beginning of the period (in shares) at Dec. 31, 2021	43,180,079	[1]		2,081,800	125,000			196,181
Condensed Consolidated Statements of Shareholders' Equity
Net income												162,565		162,565
Issuance of shares, net of offering expenses									$ 137,371
Issuance of shares, net of offering expenses (in shares)									142,500
Dividends on 7% preferred stock, annually												(2,732)
Dividends on 6% Series B preferred stock, annually												(5,625)
Dividends on 6% Series C preferred stock, annually												(8,829)
Dividends on common stock, annually												(9,066)
Other comprehensive income (loss)													(10,232)	(10,232)
Repurchase of common stock	$ (1,761)											(2,174)
Repurchase of common stock (in shares)	(165,037)
Cash paid in lieu of fractional shares for stock split	$ (1)
Cash paid in lieu of fractional shares for stock split (in shares)	(29)
Distribution to employee stock ownership plan	$ 653
Distribution to employee stock ownership plan (in shares)	20,709
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations	$ 770
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations (in shares)	73,856
Balance at end of the period at Sep. 30, 2022	$ 137,226			$ 50,221	$ 120,844			$ 191,084		$ 137,371		787,530	(11,686)	1,412,590
Balance at end of the period (in shares) at Sep. 30, 2022	43,109,578			2,081,800	125,000			196,181		142,500
Balance at beginning of the period at Jun. 30, 2022	$ 136,671	[1]		$ 50,221	$ 120,844			$ 191,084				737,789	(8,070)
Balance at beginning of the period (in shares) at Jun. 30, 2022	43,106,505	[1]		2,081,800	125,000			196,181
Condensed Consolidated Statements of Shareholders' Equity
Net income												58,488		58,488
Issuance of shares, net of offering expenses									$ 137,371
Issuance of shares, net of offering expenses (in shares)									142,500
Dividends on 7% preferred stock, annually												(911)
Dividends on 6% Series B preferred stock, annually												(1,875)
Dividends on 6% Series C preferred stock, annually												(2,943)
Dividends on common stock, annually												(3,018)
Other comprehensive income (loss)													(3,616)	(3,616)
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations	$ 555
Shares issued for stock compensation plans, net of taxes withheld to satisfy tax obligations (in shares)	3,073
Balance at end of the period at Sep. 30, 2022	$ 137,226			$ 50,221	$ 120,844			$ 191,084		$ 137,371		$ 787,530	$ (11,686)	$ 1,412,590
Balance at end of the period (in shares) at Sep. 30, 2022	43,109,578			2,081,800	125,000			196,181		142,500

[1] The number of shares and per share amounts have been restated to reflect the 3-for-2 common stock split, effective on January 17, 2022