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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
ERROR in label resolution. |  |
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

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- Definition Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563 + Details
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