Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Securities held-to-maturity, amortized cost	$ 74,610
Securities held-to-maturity, amortized cost	73,523	$ 73,711
Securities held-to-maturity, fair value	67,869	62,550
Securities held-to-maturity, gross Unrecognized losses	6,741	12,261
Securities held-to-maturity, allowance for credit losses	(1,087)	(1,100)	$ (986)	$ (862)
Securities available for sale, amortized cost, total other securities	898,819	826,881
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	811,928	735,357
Securities available for sale, gross unrealized gains	175	5
Securities available for sale, gross unrealized losses	87,066	91,529
Other Securities [Member]
Securities available for sale, amortized cost, total other securities	1,445	1,516
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	1,445	1,516
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	0	0
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	83,691	83,720
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	81,802	81,103
Securities available for sale, gross unrealized gains	171	2
Securities available for sale, gross unrealized losses	2,060	2,619
Corporate Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	173,052	146,430
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	156,581	131,766
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	16,471	14,664
US States and Political Subdivisions Debt Securities [Member]
Securities held-to-maturity, amortized cost	66,740	66,936
Securities held-to-maturity, fair value	60,732	55,561
Securities held-to-maturity, gross Unrecognized losses	6,008	11,375
Mutual Fund Debt Securities [Member]
Securities available for sale, amortized cost, total other securities	11,460	11,211
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	11,460	11,211
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	0	0
Collateralized Debt Obligations [Member]
Securities available for sale, amortized cost, total other securities	184,773	129,684
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	180,530	125,478
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	4,243	4,206
Other Debt Obligations
Securities held-to-maturity, amortized cost	66,740	66,936
Securities held-to-maturity, fair value	60,732	55,561
Securities held-to-maturity, gross Unrecognized losses	6,008	11,375
Collateralized Mortgage Backed Securities
Securities held-to-maturity, amortized cost	7,870	7,875
Securities held-to-maturity, amortized cost	7,870
Securities held-to-maturity, fair value	7,137	6,989
Securities held-to-maturity, gross Unrecognized losses	733	886
Securities available for sale, amortized cost, total other securities	444,398	454,320
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	380,110	384,283
Securities available for sale, gross unrealized gains	4	3
Securities available for sale, gross unrealized losses	64,292	70,040
REMIC and CMO [Member]
Securities available for sale, amortized cost, total other securities	172,001	175,712
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	146,318	148,414
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	25,683	27,298
GNMA [Member]
Securities available for sale, amortized cost, total other securities	9,067	9,193
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	7,304	7,317
Securities available for sale, gross unrealized gains	3	3
Securities available for sale, gross unrealized losses	1,766	1,879
FNMA [Member]
Securities held-to-maturity, amortized cost	7,870	7,875
Securities held-to-maturity, fair value	7,137	6,989
Securities held-to-maturity, gross Unrecognized losses	733	886
Securities available for sale, amortized cost, total other securities	168,689	172,690
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	146,633	148,265
Securities available for sale, gross unrealized gains	1	0
Securities available for sale, gross unrealized losses	22,057	24,425
FHLMC [Member]
Securities available for sale, amortized cost, total other securities	94,641	96,725
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	79,855	80,287
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	14,786	16,438
Available for Sale Securities Excluding Mortgage Backed Securities [Member]
Securities available for sale, amortized cost, total other securities	454,421	372,561
Securities available for sale, at fair value: (assets pledged of $193,558 and $172,235, respectively; $13,192 and $13,023 at fair value pursuant to the fair value option, respectively)	431,818	351,074
Securities available for sale, gross unrealized gains	171	2
Securities available for sale, gross unrealized losses	$ 22,774	$ 21,489

Amount of investment in debt security measured at amortized cost, before allowance for credit losses.

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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).

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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).

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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).

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