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Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
AFS Debt Securities: |  |  |
Unrealized holdings losses, pre-tax amount | $ (38,832) | $ 33,198 | $ 26,743
Unrealized holdings losses, tax (expense) benefit | 8,349 | (7,138) | (5,750)
Unrealized holdings losses, after-tax amount | (30,483) | 26,060 | 20,993
Less: reclassification adjustment for realized losses, pre-tax amount | 0 | 0 | (105)
Less: reclassification adjustment for realized losses, tax (expense) benefit | 0 | 0 | 22
Less: reclassification adjustment for realized losses, after-tax amount | 0 | 0 | (83)
Net unrealized losses, pre-tax amount | (38,832) | 33,198 | 26,848
Net unrealized losses, tax (expense) benefit | 8,349 | (7,138) | (5,772)
Net unrealized losses, after-tax amount | (30,483) | 26,060 | 21,076
Cash Flow Hedges: |  |  |
Net increase in fair value, pre-tax amount | 2,987 | 1,214 | (2,973)
Net increase in fair value, tax (expense) benefit | (642) | (260) | 639
Net increase in fair value, after-tax amount | 2,345 | 954 | (2,334)
Net increase in fair value, pre-tax amount | 3,627 | 1,811 | (2,052)
Net increase in fair value, tax (expense) benefit | (780) | (389) | 441
Net increase in fair value, after-tax amount | 2,847 | 1,422 | (1,611)
Postretirement Plans: |  |  |
Net actuarial loss, pre-tax amount | (20) | (1,282) | (1,918)
Net actuarial loss, tax (expense) benefit | 4 | 277 | 412
Net actuarial loss, after-tax amount | (16) | (1,005) | (1,506)
Less: Amortization of net actuarial losses, pre-tax amount | (894) | (701) | (271)
Less: Amortization of net actuarial losses, tax (expense) benefit | 192 | 151 | 59
Less: Amortization of net prior service credits, after-tax amount | (702) | (550) | (212)
Less: Amortization of net prior service credits, pre-tax amount | 24 | 24 | 24
Less: Amortization of net prior service credits, tax (expense) benefit | (5) | (5) | (5)
Less: Amortization of net prior service credits, after-tax amount | 19 | 19 | 19
Net loss on postretirement plans, pre-tax amount | 850 | (605) | (1,671)
Net loss on postretirement plans, tax (expense) benefit | (183) | 131 | 358
Net (loss) gain on postretirement plans, net of tax | 667 | (474) | (1,313)
Other comprehensive income, pre-tax amount | (34,355) | 34,404 | 23,125
Other comprehensive income, tax (expense) benefit | 7,386 | (7,396) | (4,973)
Other comprehensive (loss) income | (26,969) | 27,008 | 18,152
Interest Expense, Borrowings and Subordinated Debentures |  |  |
Cash Flow Hedges: |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | (2,254) | (1,603) | (707)
Less: effective portion reclassified into interest expense, tax (expense) benefit | 485 | 345 | 151
Less: effective portion reclassified into interest expense, after-tax amount | (1,769) | (1,258) | (556)
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | (2,254) | (1,603) | (707)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax | (485) | (345) | (151)
Less: Amounts reclassified from AOCI | (1,769) | (1,258) | (556)
Interest Income, Interest and Fees on Loans |  |  |
Cash Flow Hedges: |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | 1,614 | 1,006 | (214)
Less: effective portion reclassified into interest expense, tax (expense) benefit | (347) | (216) | 47
Less: effective portion reclassified into interest expense, after-tax amount | 1,267 | 790 | (167)
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Less: effective portion reclassified into interest expense, pre-tax amount | 1,614 | 1,006 | (214)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax | 347 | 216 | (47)
Less: Amounts reclassified from AOCI | $ 1,267 | $ 790 | $ (167)

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