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Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Commitments to Extend Credit |  |
Letters of credit | $ 2,530,000 | $ 2,290,000
Allowance for unfunded credit commitments | 33,600 | 26,200
Loans Sold or Securitized With Recourse | Single Family and Multi-family Residential Loans | Loans Sold or Securitized with Recourse |  |
Commitments to Extend Credit |  |
Allowance for unfunded credit commitments | 35 | 37
Standby Letters of Credit |  |
Commitments to Extend Credit |  |
Letters of credit | 2,500,000 | 2,270,000
Commercial Letters of Credit |  |
Commitments to Extend Credit |  |
Letters of credit | $ 32,700 | $ 21,600

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