Commitments and Contingencies - Schedule of the Contractual Amount of Significant Commitments (Details) - USD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
|---|---|---|---|---|
| Other Commitments [Line Items] | ||||
| Stand-by letters of credit | $ 628 | $ 803 | ||
| Total commitments | 11,311 | 13,843 | ||
| Allowance for credit losses on loans and leases | 1,030 | 1,201 | $ 992 | $ 393 |
| Total loan commitments | ||||
| Other Commitments [Line Items] | ||||
| Allowance for credit losses on loans and leases | 55 | 50 | ||
| Total loan commitments | ||||
| Other Commitments [Line Items] | ||||
| Total loan commitments | 10,683 | 13,040 | ||
| Multi-family and commercial real estate | ||||
| Other Commitments [Line Items] | ||||
| Total loan commitments | 553 | 2,478 | ||
| One-to-four family including interest rate locks | ||||
| Other Commitments [Line Items] | ||||
| Total loan commitments | 1,031 | 725 | ||
| Other loan commitments | ||||
| Other Commitments [Line Items] | ||||
| Total loan commitments | $ 9,099 | $ 9,837 |