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v3.21.1

Commitments and Contingencies (Detail) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) shares | Dec. 31, 2020 USD ($)
Loss Contingencies [Line Items] |  |
Loan commitments | $ 3,851,000,000 | $ 3,720,000,000
Standby letters of credit | 75,100,000 | 86,900,000
Fixed rate loan commitment | 3,613,000,000 |
Floating rate loan commitment | $ 238,300,000 |
Loan commitments floating rate, minimum | 0.00% |
Loan commitments floating rate, maximum | 14.00% |
Allowance for unfunded loan commitments | $ 10,400,000 | 11,700,000
Extended credit | 7,900,000 | 7,900,000
Credit extensions with collateral | $ 7,500,000 | $ 7,500,000
Class B Restricted Shares | Visa |  |
Loss Contingencies [Line Items] |  |
Restricted stock conversion ratio | 1.6228 |
Investment owned, balance, shares | shares | 65,466 |
Investment owned, at cost | $ 0 |

X
- Definition Amount of valuation allowance recorded for unfunded commitments to extend credit. + References No definition available. + Details
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- Definition Amount of credit extended with unaffiliated banks related to letter of credit commitments issued on behalf of our clients. + References No definition available. + Details
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- Definition Amount of collateral provided to secure credit extended with unaffiliated banks related to letter of credit commitments issued on behalf of our clients. + References No definition available. + Details
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- Definition Maximum floating rate percentage charged on loan commitments. + References No definition available. + Details
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- Definition Minimum floating rate percentage charged on loan commitments. + References No definition available. + Details
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- Definition Amount of agreement to extend credit in the form of a standby letter of credit. + References No definition available. + Details
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- Definition Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at stated interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 825 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61044-112788 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 825 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61082-112788 + Details
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