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Commitments and Contingencies (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Commitments And Contingencies [Line Items] |  |  |
Letters of credit outstanding | $ 344,400 | $ 351,100 |
Mortgage loans sold | 3,146,442 | 7,441,705 | $ 7,624,799
Liability for estimated losses on repurchase and indemnification claims | 624 | 675 |
Losses charged against liability | 60 | 219 |
Unfunded commitments to investment partnerships | 50,900 | 40,300 |
Commitments to invest in partnership for tax credits | 7,100 |  |
Customer balances maintained by clearing broker and subject to indemnification | 15,800 | 22,500 |
Forward contracts |  |  |
Commitments And Contingencies [Line Items] |  |  |
Derivative instrument, contractual amounts | 321,000 | 952,300 |
Commercial, commercial real estate, and construction loans | Commitments to extend credit |  |  |
Commitments And Contingencies [Line Items] |  |  |
Commitments to fund | 9,500,000 | 7,800,000 |
Unused home equity lines | Commitments to extend credit |  |  |
Commitments And Contingencies [Line Items] |  |  |
Commitments to fund | 796,900 | 749,400 |
Residential real estate | Commitments to extend credit |  |  |
Commitments And Contingencies [Line Items] |  |  |
Commitments to fund | $ 181,000 | $ 590,000 |

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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959 + Details
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
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- Definition The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21 -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3461-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3536-108585 + Details
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- Definition Amount of commitment or contingent commitments to qualified affordable housing project investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 740 -Section 50 -Paragraph 2 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985 + Details
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- Definition Commitments and contingencies [Line Items]. + References No definition available. + Details
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- Definition Customer balances maintained by clearing broker and subject to indemnification. + References No definition available. + Details
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- Definition Liability for loss indemnification claims on residential mortgage loans previously sold to investors. + References No definition available. + Details
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- Definition Unfunded Commitments To Invest In Partnerships + References No definition available. + Details
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