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Deposits - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Statistical Disclosure for Banks [Abstract] |  |  |
Time deposits with a denomination of $250,000 or more | $ 2,220 | $ 593 |
Deposit Liability [Line Items] |  |  |
Deposits | 89,408 | $ 51,406 | $ 43,432
Digital Bank |  |  |
Deposit Liability [Line Items] |  |  |
Deposits | $ 16,470 |  |
Deposits | Customer Concentration Risk | Digital Bank |  |  |
Deposit Liability [Line Items] |  |  |
Concentration risk, percentage |  | 18.40% |
North Carolina | Deposits | Geographic Concentration Risk |  |  |
Deposit Liability [Line Items] |  |  |
Concentration risk, percentage | 39.70% | 50.80% |
South Carolina | Deposits | Geographic Concentration Risk |  |  |
Deposit Liability [Line Items] |  |  |
Concentration risk, percentage | 13.30% | 22.70% |

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