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Investment Securities - Held-to-Maturity Amortized Cost and Fair Value (Details) - USD ($) | Jun. 30, 2021 | Dec. 31, 2020
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | $ 169,038,000 | $ 109,036,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 169,038,000 | 109,036,000
Held-to-maturity, gross unrealized gains | 5,138,000 | 6,149,000
Held-to-maturity, gross unrealized losses | (38,000) | 0
Held to maturity, fair value | 174,138,000 | 115,185,000
Accrued interest | 550,000 | 366,000
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost |  | 0
Allowance for Credit Losses |  | 0
Net Carrying Amount |  | 0
Held-to-maturity, gross unrealized gains |  | 0
Held-to-maturity, gross unrealized losses |  | 0
Held to maturity, fair value |  | 0
MBS pass-through securities issued by FHLMC and FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 74,115,000 | 65,579,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 74,115,000 | 65,579,000
Held-to-maturity, gross unrealized gains | 3,247,000 | 3,924,000
Held-to-maturity, gross unrealized losses | 0 | 0
Held to maturity, fair value | 77,362,000 | 69,503,000
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 38,641,000 | 27,201,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 38,641,000 | 27,201,000
Held-to-maturity, gross unrealized gains | 1,142,000 | 1,441,000
Held-to-maturity, gross unrealized losses | (38,000) | 0
Held to maturity, fair value | 39,745,000 | 28,642,000
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 6,274,000 | 8,042,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 6,274,000 | 8,042,000
Held-to-maturity, gross unrealized gains | 265,000 | 363,000
Held-to-maturity, gross unrealized losses | 0 | 0
Held to maturity, fair value | 6,539,000 | 8,405,000
SBA-backed securities |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 5,697,000 | 6,547,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 5,697,000 | 6,547,000
Held-to-maturity, gross unrealized gains | 361,000 | 400,000
Held-to-maturity, gross unrealized losses | 0 | 0
Held to maturity, fair value | 6,058,000 | 6,947,000
Debentures of government- sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 43,731,000 |
Allowance for Credit Losses | 0 |
Net Carrying Amount | 43,731,000 |
Held-to-maturity, gross unrealized gains | 115,000 |
Held-to-maturity, gross unrealized losses | 0 |
Held to maturity, fair value | 43,846,000 |
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held to maturity, amortized cost | 580,000 | 1,667,000
Allowance for Credit Losses | 0 | 0
Net Carrying Amount | 580,000 | 1,667,000
Held-to-maturity, gross unrealized gains | 8,000 | 21,000
Held-to-maturity, gross unrealized losses | 0 | 0
Held to maturity, fair value | $ 588,000 | $ 1,688,000

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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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