Securities - Amortized Cost and Fair Value, Held to Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 1,353,534	$ 416,389
Gross Unrealized Gains	0	334
Gross Unrealized Losses	(134,878)	(1,171)
Fair Value	1,218,656	415,552
Allowance for credit losses - held to maturity securities	(32)	(32)
Held to maturity securities, net of allowance for credit losses	1,353,502	416,357
Obligations of states and political subdivisions
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	292,769	267,641
Gross Unrealized Gains	0	333
Gross Unrealized Losses	(63,602)	(685)
Fair Value	229,167	267,289
Residential mortgage backed securities:
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	433,407	24,832
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(27,038)	(92)
Fair Value	406,369	24,740
Other debt securities
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	65,344	22,049
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(5,331)	(79)
Fair Value	60,013	21,970
Government agency mortgage backed securities \| Residential mortgage backed securities:
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	499,348	60,507
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(29,278)	(198)
Fair Value	470,070	60,310
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	17,011	1,855
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(3,429)	0
Fair Value	13,582	1,855
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	45,655	39,505
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(6,200)	(117)
Fair Value	$ 39,455	$ 39,388

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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