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v3.22.4

Summary of Significant Accounting Policies - Narrative (Details) | 12 Months Ended
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Dec. 31, 2022 USD ($) segment subsidiary | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Property, Plant and Equipment |  |  |
Deficiency (benefit) of stock-based compensation plans | $ 200,000 | $ (500,000) | $ (400,000)
Impairment losses | $ 0 | 0 | 0
Number of significant subsidiaries | subsidiary | 1 |  |
Income tax examination, penalties | $ 0 | 0 | 0
Cash on deposit with Federal Reserve Bank | 518,900,000 | 2,166,100,000 |
Federal Reserve Bank stock | 93,600,000 | 42,800,000 |
Federal Home Loan Bank stock | 103,800,000 | 10,600,000 |
Advertising expense | 3,800,000 | 2,600,000 | $ 2,800,000
Loans and Leases Receivable Disclosure [Line Items] |  |  |
Accrued interest receivable | 118,300,000 | 47,400,000 |
Accrued Investment Income Receivable | 38,900,000 | 16,600,000 |
Hosting Arrangement, Service Contract, Implementation Cost, Expense, Amortization | $ 3,400,000 | 4,600,000 |
Number of operating segments | segment | 1 |  |
Total investment securities | $ 1,200,000 | 400,000 |
Buildings and improvements | Minimum |  |  |
Property, Plant and Equipment |  |  |
Estimated useful lives | 5 years |  |
Buildings and improvements | Maximum [Member] |  |  |
Property, Plant and Equipment |  |  |
Estimated useful lives | 45 years |  |
Furniture and equipment | Minimum |  |  |
Property, Plant and Equipment |  |  |
Estimated useful lives | 3 years |  |
Furniture and equipment | Maximum [Member] |  |  |
Property, Plant and Equipment |  |  |
Estimated useful lives | 15 years |  |
Loans |  |  |
Loans and Leases Receivable Disclosure [Line Items] |  |  |
Accrued interest receivable | $ 76,500,000 | $ 30,200,000 |

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