| DerivativeAssetAfterOffsetSubjectToMasterNettingArrangement | 70.00M | as of 2025-12-31 |
| Derivative Asset, Not Offset, Policy Election Deduction | 0 | as of 2025-12-31 |
| Dividends, Preferred Stock | 1.00M | 2025-10-01 → 2025-12-31 |
| Participating Securities, Distributed and Undistributed Earnings (Loss), Basic | 1.00M | 2025-10-01 → 2025-12-31 |
| Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset | 225.00M | as of 2025-12-31 |
| Securities Purchased under Agreements to Resell, Gross | 311.00M | as of 2025-12-31 |
| Securities Purchased under Agreements to Resell, Liability | 0 | as of 2025-12-31 |
| SecurityPurchasedUnderAgreementToResellAfterOffsetSubjectToMasterNettingArrangement | 311.00M | as of 2025-12-31 |
| Fair Value of Securities Received as Collateral that Can be Resold or Repledged | 4.35B | as of 2025-12-31 |
| Securities Purchased under Agreements to Resell, Not Offset, Policy Election Deduction | 311.00M | as of 2025-12-31 |
| Fair Value of Securities Received as Collateral that Have Been Resold or Repledged | 1.66B | as of 2025-12-31 |
| SecurityPurchasedUnderAgreementToResellAfterOffsetAndDeductionSubjectToMasterNettingArrangement | 0 | as of 2025-12-31 |
| Loss Contingency, Range of Possible Loss, Portion Not Accrued | 10.00M | as of 2025-12-31 |
| Securities Borrowed, Gross | 429.00M | as of 2025-12-31 |
| Securities Borrowed, Liability | 0 | as of 2025-12-31 |
| SecurityBorrowedAfterOffsetSubjectToMasterNettingArrangement | 429.00M | as of 2025-12-31 |
| Securities Borrowed, Not Offset, Policy Election Deduction | 415.00M | as of 2025-12-31 |
| SecurityBorrowedAfterOffsetAndDeductionSubjectToMasterNettingArrangement | 14.00M | as of 2025-12-31 |
| SegmentReportingOtherItemAmount | 560.00M | 2025-10-01 → 2025-12-31 |
| Net Income (Loss) Attributable to Parent, Diluted | 561.00M | 2025-10-01 → 2025-12-31 |
| TimeDepositLiabilityUninsuredMaturityThreeMonthsOrLess | 60.00M | as of 2025-12-31 |
| TimeDepositLiabilityUninsuredMaturityOverThreeMonthsThroughSixMonths | 44.00M | as of 2025-12-31 |
| TimeDepositLiabilityUninsuredMaturityOverSixMonthsThroughTwelveMonths | 34.00M | as of 2025-12-31 |
| TimeDepositLiabilityUninsuredMaturityOverTwelveMonths | 24.00M | as of 2025-12-31 |
| Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed, Gross | 740.00M | as of 2025-12-31 |
| TimeDepositLiabilityUninsured | 162.00M | as of 2025-12-31 |
| Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed, Liability | 0 | as of 2025-12-31 |
| Participating Securities, Distributed and Undistributed Earnings (Loss), Diluted | 1.00M | 2025-10-01 → 2025-12-31 |
| DerivativeAssetSecurityPurchasedUnderAgreementToResellSecurityBorrowedAfterOffsetSubjectToMasterNettingArrangement | 740.00M | as of 2025-12-31 |
| Derivative Asset, Securities Purchased under Agreements to Resell, Securities Borrowed, Not Offset, Policy Election Deduction | 726.00M | as of 2025-12-31 |
| DerivativeAssetSecurityPurchasedUnderAgreementToResellSecurityBorrowedAfterOffsetAndDeductionSubjectToMasterNettingArrangement | 14.00M | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One | 649.00M | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five | 1.38B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 | 1.74B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 | 3.34B | as of 2025-12-31 |
| Derivative Asset, Fair Value, Gross Liability | 91.00M | as of 2025-12-31 |
| DerivativeLiabilityAfterOffsetSubjectToMasterNettingArrangement | 181.00M | as of 2025-12-31 |
| Derivative Liability, Fair Value, Gross Asset | 91.00M | as of 2025-12-31 |
| Net Income (Loss) Available to Common Stockholders, Diluted | 562.00M | 2025-10-01 → 2025-12-31 |
| Derivative Liability, Not Offset, Policy Election Deduction | 0 | as of 2025-12-31 |
| Derivative, Notional Amount | 23.38B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One | 647.00M | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five | 1.31B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 | 1.62B | as of 2025-12-31 |
| Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 | 3.08B | as of 2025-12-31 |
| Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset | 122.00M | as of 2025-12-31 |
| Stock Repurchase Program, Remaining Authorized Repurchase Amount | 1.90B | as of 2025-12-31 |
| Securities Sold under Agreements to Repurchase, Gross | 368.00M | as of 2025-12-31 |
| Securities Sold under Agreements to Repurchase, Asset | 0 | as of 2025-12-31 |
| SecuritySoldUnderAgreementToRepurchaseAfterOffsetSubjectToMasterNettingArrangement | 368.00M | as of 2025-12-31 |
| Securities Sold under Agreements to Repurchase, Not Offset, Policy Election Deduction | 368.00M | as of 2025-12-31 |
| Intangible Assets, Net (Including Goodwill) | 1.84B | as of 2025-12-31 |
| SecuritySoldUnderAgreementToRepurchaseAfterOffsetAndDeductionSubjectToMasterNettingArrangement | 0 | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 477.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 477.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 11.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 477.00M | as of 2025-12-31 |
| Time Deposit Maturities, Year One | 400.00M | as of 2025-12-31 |
| Time Deposit Maturities, Year Two | 119.00M | as of 2025-12-31 |
| Securities Loaned, Gross | 514.00M | as of 2025-12-31 |
| Time Deposit Maturities, Year Three | 49.00M | as of 2025-12-31 |
| Securities Loaned, Asset | 0 | as of 2025-12-31 |
| Time Deposit Maturities, Year Four | 39.00M | as of 2025-12-31 |
| SecurityLoanedAfterOffsetSubjectToMasterNettingArrangement | 514.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 185.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 5.44B | as of 2025-12-31 |
| Securities Loaned, Not Offset, Policy Election Deduction | 492.00M | as of 2025-12-31 |
| Debt Securities, Available-for-sale, Unrealized Loss Position | 5.63B | as of 2025-12-31 |
| SecurityLoanedAfterOffsetAndDeductionSubjectToMasterNettingArrangement | 22.00M | as of 2025-12-31 |
| Derivative Asset, Fair Value, Amount Offset Against Collateral | 70.00M | as of 2025-12-31 |
| Derivative Liability, Fair Value, Amount Offset Against Collateral | 181.00M | as of 2025-12-31 |
| Stock Repurchased During Period, Value | 400.00M | 2025-10-01 → 2025-12-31 |
| Time Deposit Maturities, Remainder of Fiscal Year | 1.36B | as of 2025-12-31 |
| Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Gross | 882.00M | as of 2025-12-31 |
| Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Asset | 0 | as of 2025-12-31 |
| DerivativeLiabilitySecuritySoldUnderAgreementToRepurchaseSecurityLoanedAfterOffsetSubjectToMasterNettingArrangement | 882.00M | as of 2025-12-31 |
| Derivative Liability, Securities Sold under Agreements to Repurchase, Securities Loaned, Not Offset, Policy Election Deduction | 860.00M | as of 2025-12-31 |
| DerivativeLiabilitySecuritySoldUnderAgreementToRepurchaseSecurityLoanedAfterOffsetAndDeductionSubjectToMasterNettingArrangement | 22.00M | as of 2025-12-31 |
| Operating Lease, Cost | 37.00M | 2025-10-01 → 2025-12-31 |
| Variable Lease, Cost | 9.00M | 2025-10-01 → 2025-12-31 |
| Right-of-Use Asset Obtained in Exchange for Operating Lease Liability | 19.00M | 2025-10-01 → 2025-12-31 |
| Derivative Liability, Collateral, Right to Reclaim Cash, Offset | 31.00M | as of 2025-12-31 |
| Interest Expense Domestic Deposit Liabilities, Checking | 203.00M | 2025-10-01 → 2025-12-31 |
| Derivative Asset, Collateral, Obligation to Return Cash, Offset | 134.00M | as of 2025-12-31 |
| Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net | 0 | 2025-10-01 → 2025-12-31 |
| Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net | -6.00M | as of 2025-12-31 |
| Decrease in Unrecognized Tax Benefits is Reasonably Possible | 12.00M | as of 2025-12-31 |
| Other Receivables | 1.49B | as of 2025-12-31 |
| Advances from Federal Home Loan Banks | 700.00M | as of 2025-12-31 |
| Derivative Liability, Fair Value, Gross Liability | 303.00M | as of 2025-12-31 |
| Derivative Asset, Fair Value, Gross Asset | 295.00M | as of 2025-12-31 |