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Derivative Financial Instruments - Narrative (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Time-value premiums | $ 500 | $ 2,300 | $ 3,600
Cash collateral pledged | 80 | 0 |
Current net credit exposure | 19,000 |  |
Non-performance risk in fair value measurement | 7,600 | $ 6,200 |
Cash and Due from Banks |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Cash collateral pledged | 100 |  |
Price Risk Derivative |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Remaining unamortized gain (loss) | 0 |  |
CME Swaps Markets |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Initial margin posted at clearing house | 1,700 |  |
Valuation, Cost Approach |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Cash collateral pledged | 256,200 |  |
Valuation, Market Approach |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Current net credit exposure | 109,200 |  |
Cash Flow Hedging |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Estimate of amount to be reclassified from AOCL | $ (5,200) |  |
Maximum time for forecasted transactions | 2 years 2 months 12 days |  |

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- Definition Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-11 + Details
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- Definition Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4K -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4K + Details
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- Definition Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 5 -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480463/815-10-45-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -SubTopic 20 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483466/210-20-50-3 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4E -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4E + Details
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- Definition The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480870/815-30-50-1 + Details
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- Definition Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -SubTopic 30 -Topic 815 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480870/815-30-50-1 + Details
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