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Investment Securities - Held-to-Maturity Securities Amortized Cost and Fair Value (Details) - USD ($) | Dec. 31, 2021 | Dec. 31, 2020
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Debt Securities, Held-to-maturity [Abstract] |  |  |
Amortized Cost |  | $ 342,222,000 | $ 109,036,000
Allowance for Credit Losses | [1] | 0 | 0
Net Carrying Amount |  | 342,222,000 | 109,036,000
Gross Unrealized Gains |  | 3,400,000 | 6,149,000
Gross Unrealized (Losses) |  | (2,867,000) | 0
Fair Value |  | 342,755,000 | 115,185,000
Other assets |  |  |
Debt Securities, Held-to-maturity [Abstract] |  |  |
Accrued interest |  | 1,100,000 | 366,000
MBS pass-through securities issued by FHLMC and FNMA |  |  |
Debt Securities, Held-to-maturity [Abstract] |  |  |
Amortized Cost |  | 126,990,000 | 65,579,000
Allowance for Credit Losses |  | 0 | 0
Net Carrying Amount |  | 126,990,000 | 65,579,000
Gross Unrealized Gains |  | 2,110,000 | 3,924,000
Gross Unrealized (Losses) |  | (712,000) | 0
Fair Value |  | 128,388,000 | 69,503,000
CMOs issued by FHLMC |  |  |
Debt Securities, Held-to-maturity [Abstract] |  |  |
Amortized Cost |  | 106,851,000 | 27,201,000
Allowance for Credit Losses |  | 0 | 0
Net Carrying Amount |  | 106,851,000 | 27,201,000
Gross Unrealized Gains |  | 668,000 | 1,441,000
Gross Unrealized (Losses) |  | (1,045,000) | 0
Fair Value |  | 106,474,000 | 28,642,000
CMOs issued by FNMA |  |  |
Debt Securities, Held-to-maturity [Abstract] |  |  |
Amortized Cost |  | 4,866,000 | 8,042,000
Allowance for Credit Losses |  | 0 | 0
Net Carrying Amount |  | 4,866,000 | 8,042,000
Gross Unrealized Gains |  | 128,000 | 363,000
Gross Unrealized (Losses) |  | 0 | 0
Fair Value |  | 4,994,000 | 8,405,000
SBA-backed securities |  |  |
Debt Securities, Held-to-maturity [Abstract] |  |  |
Amortized Cost |  | 4,840,000 | 6,547,000
Allowance for Credit Losses |  | 0 | 0
Net Carrying Amount |  | 4,840,000 | 6,547,000
Gross Unrealized Gains |  | 198,000 | 400,000
Gross Unrealized (Losses) |  | 0 | 0
Fair Value |  | 5,038,000 | 6,947,000
Debentures of government sponsored agencies |  |  |
Debt Securities, Held-to-maturity [Abstract] |  |  |
Amortized Cost |  | 51,472,000 |
Allowance for Credit Losses |  |  |
Net Carrying Amount |  | 51,472,000 |
Gross Unrealized Gains |  | 0 |
Gross Unrealized (Losses) |  | (901,000) |
Fair Value |  | 50,571,000 |
Obligations of state and political subdivisions |  |  |
Debt Securities, Held-to-maturity [Abstract] |  |  |
Amortized Cost |  | 47,203,000 | 1,667,000
Allowance for Credit Losses |  | 0 | 0
Net Carrying Amount |  | 47,203,000 | 1,667,000
Gross Unrealized Gains |  | 296,000 | 21,000
Gross Unrealized (Losses) |  | (209,000) | 0
Fair Value |  | $ 47,290,000 | $ 1,688,000
[1] | Refer to Note 1, Summary of Accounting Policies, for information on the adoption of ASU 2016-13 in 2020.

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- Definition Amount, before allowance for credit loss, of accrued interest on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3B -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447 + Details
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