Investment Securities - Amortized Cost and Fair Values of Debt Securities Held to Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 541,311	$ 361,844
Gross Unrealized Gains	3,768	8,017
Gross Unrealized Losses	(8,428)	(10)
Estimated Fair Value	536,651	369,851
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Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	1,000	800
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(3)	0
Estimated Fair Value	997	800
US States and Political Subdivisions Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	29,402	34,391
Gross Unrealized Gains	414	705
Gross Unrealized Losses	(103)	0
Estimated Fair Value	29,713	35,096
Mortgage - Backed Securities - Commercial [Member] \| Obligations of U.S. Government [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	91,439	36,799
Gross Unrealized Gains	305	1,441
Gross Unrealized Losses	(1,939)	0
Estimated Fair Value	89,805	38,240
Mortgage - Backed Securities - Commercial [Member] \| Obligations of U.S. Government-Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	7,309	9,737
Gross Unrealized Gains	148	344
Gross Unrealized Losses	0	0
Estimated Fair Value	7,457	10,081
Mortgage - Backed Securities - Residential [Member] \| Obligations of U.S. Government [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	2,409	2,766
Gross Unrealized Gains	101	138
Gross Unrealized Losses	0	0
Estimated Fair Value	2,510	2,904
Mortgage - Backed Securities - Residential [Member] \| Obligations of U.S. Government-Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	387,848	277,351
Gross Unrealized Gains	2,800	5,389
Gross Unrealized Losses	(5,758)	(10)
Estimated Fair Value	384,890	282,730
Other Government - Sponsored Enterprises [Member] \| Obligations of U.S. Government-Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	21,904	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(625)	0
Estimated Fair Value	$ 21,279	$ 0

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

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