Securities - Amortized Cost and Fair Value of Securities Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Amortized cost and fair value of securities available for sale
Amortized Cost	$ 1,130,119	$ 1,735,000
Gross Unrealized Gains	360	241
Gross Unrealized Losses	(179,549)	(201,299)
Fair Value	950,930	1,533,942
Obligations of other U.S. Government agencies and corporations
Amortized cost and fair value of securities available for sale
Amortized Cost		170,000
Gross Unrealized Gains		0
Gross Unrealized Losses		(5,340)
Fair Value		164,660
Obligations of states and political subdivisions
Amortized cost and fair value of securities available for sale
Amortized Cost	41,474	154,066
Gross Unrealized Gains	16	204
Gross Unrealized Losses	(3,439)	(9,368)
Fair Value	38,051	144,902
Residential mortgage backed securities: \| Government agency mortgage backed securities
Amortized cost and fair value of securities available for sale
Amortized Cost	328,760	508,415
Gross Unrealized Gains	28	37
Gross Unrealized Losses	(42,751)	(52,036)
Fair Value	286,037	456,416
Residential mortgage backed securities: \| Government agency collateralized mortgage obligations
Amortized cost and fair value of securities available for sale
Amortized Cost	516,474	605,033
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(101,385)	(103,864)
Fair Value	415,089	501,169
Commercial mortgage backed securities: \| Government agency mortgage backed securities
Amortized cost and fair value of securities available for sale
Amortized Cost	6,042	11,166
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(797)	(1,053)
Fair Value	5,245	10,113
Commercial mortgage backed securities: \| Government agency collateralized mortgage obligations
Amortized cost and fair value of securities available for sale
Amortized Cost	164,320	211,435
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(25,508)	(25,589)
Fair Value	138,812	185,846
Other debt securities
Amortized cost and fair value of securities available for sale
Amortized Cost	73,049	74,885
Gross Unrealized Gains	316	0
Gross Unrealized Losses	(5,669)	(4,049)
Fair Value	$ 67,696	$ 70,836

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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