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Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Investment Holdings [Line Items] |  |
Amortized cost | $ 480,784 | $ 375,579
Gross unrealized gains | 1,124 | 7,065
Gross unrealized losses | (14,925) | (1,927)
Estimated fair value | 466,983 | 380,717
US Treasury Securities [Member] |  |
Investment Holdings [Line Items] |  |
Amortized cost | 123,615 | 43,098
Gross unrealized gains |  |
Gross unrealized losses | (3,733) | (423)
Estimated fair value | 119,882 | 42,675
U.S. Federal Agency Obligations [Member] |  |
Investment Holdings [Line Items] |  |
Amortized cost | 17,118 | 17,165
Gross unrealized gains | 24 | 67
Gross unrealized losses | (129) | (37)
Estimated fair value | 17,013 | 17,195
Municipal Obligations, Tax Exempt [Member] |  |
Investment Holdings [Line Items] |  |
Amortized cost | 131,565 | 133,558
Gross unrealized gains | 780 | 4,488
Gross unrealized losses | (1,430) | (62)
Estimated fair value | 130,915 | 137,984
Municipal Obligations, Taxable [Member] |  |
Investment Holdings [Line Items] |  |
Amortized cost | 46,733 | 39,011
Gross unrealized gains | 305 | 1,171
Gross unrealized losses | (1,452) | (136)
Estimated fair value | 45,586 | 40,046
Agency Mortgage-backed Securities [Member] |  |
Investment Holdings [Line Items] |  |
Amortized cost | 161,753 | 142,747
Gross unrealized gains | 15 | 1,339
Gross unrealized losses | (8,181) | (1,269)
Estimated fair value | $ 153,587 | $ 142,817

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