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Qualified Affordable Housing Project Investments - Additional Information (Detail) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
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Sep. 30, 2025 | Dec. 31, 2024
Equity Method Investments and Joint Ventures [Abstract] |  |
Qualified affordable housing project investments | $ 3,200 | $ 3,600
Funded balance in qualified affordable housing projects | 3,570 | 3,120
Funded commitments related to the investments in qualified affordable housing projects | 4,000 | 4,000
Unfunded commitments related to the investments in qualified affordable housing projects | $ 430 | $ 880
Investment, Proportional Amortization Method, Elected, Statement of Financial Position [Extensible Enumeration] | Other Assets | Other Assets
Impairment losses related to investments in qualified affordable housing projects | no | no

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- Definition Funded commitments related to the investments in qualified affordable housing projects. + References No definition available. + Details
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- Definition Unfunded commitments related to the investments in qualified affordable housing projects. + References No definition available. + Details
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- Definition Description of nature of impairment loss for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-2 + Details
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- Definition Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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- Definition Indicates line item in statement of financial position that includes investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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- Definition Amount of commitment and contingent commitment, including amount of delayed equity contribution, for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, commitment and contingent commitment related to investment under tax credit program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-2 + Details
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