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v3.25.1

Investment Securities - Summary of Unrealized Loss Positions on Investment Securities (Details) $ in Millions | Mar. 31, 2025 USD ($) security | Dec. 31, 2024 USD ($) security
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 604,000,000 | 609,000,000
Fair Value |  |
Less than Twelve Months | $ 2,973 | $ 1,674
Twelve Months or Longer | 5,505 | 5,592
Total | 8,478 | 7,266
Unrealized Loss |  |
Less than Twelve Months | 10 | 3
Twelve Months or Longer | 825 | 929
Total | $ 835 | $ 932
Debt Securities | GSE CMOs |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 221,000,000 | 223,000,000
Fair Value |  |
Less than Twelve Months | $ 1,869 | $ 1,636
Twelve Months or Longer | 2,829 | 2,822
Total | 4,698 | 4,458
Unrealized Loss |  |
Less than Twelve Months | 7 | 3
Twelve Months or Longer | 398 | 444
Total | $ 405 | $ 447
Debt Securities | U.S. Government agency and GSE obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 33,000,000 | 33,000,000
Fair Value |  |
Less than Twelve Months | $ 0 | $ 0
Twelve Months or Longer | 1,241 | 1,203
Total | 1,241 | 1,203
Unrealized Loss |  |
Less than Twelve Months | 0 | 0
Twelve Months or Longer | 261 | 299
Total | $ 261 | $ 299
Debt Securities | GSE certificates |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 328,000,000 | 328,000,000
Fair Value |  |
Less than Twelve Months | $ 11 | $ 38
Twelve Months or Longer | 1,045 | 1,040
Total | 1,056 | 1,078
Unrealized Loss |  |
Less than Twelve Months | 0 | 0
Twelve Months or Longer | 145 | 167
Total | $ 145 | $ 167
Debt Securities | U. S. Treasury obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 0 |
Fair Value |  |
Less than Twelve Months | $ 1,001 |
Twelve Months or Longer | 0 |
Total | 1,001 |
Unrealized Loss |  |
Less than Twelve Months | 1 |
Twelve Months or Longer | 0 |
Total | $ 1 |
Debt Securities | Corporate bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 8,000,000 | 11,000,000
Fair Value |  |
Less than Twelve Months | $ 73 | $ 0
Twelve Months or Longer | 175 | 308
Total | 248 | 308
Unrealized Loss |  |
Less than Twelve Months | 2 | 0
Twelve Months or Longer | 8 | 6
Total | $ 10 | $ 6
Debt Securities | Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 5,000,000 | 5,000,000
Fair Value |  |
Less than Twelve Months | $ 15 | $ 0
Twelve Months or Longer | 150 | 154
Total | 165 | 154
Unrealized Loss |  |
Less than Twelve Months | 0 | 0
Twelve Months or Longer | 3 | 2
Total | $ 3 | $ 2
Debt Securities | Capital trust notes |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 5,000,000 | 5,000,000
Fair Value |  |
Less than Twelve Months | $ 0 | $ 0
Twelve Months or Longer | 34 | 33
Total | 34 | 33
Unrealized Loss |  |
Less than Twelve Months | 0 | 0
Twelve Months or Longer | 9 | 10
Total | $ 9 | $ 10
Debt Securities | Private Label collateralized mortgage obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 2,000,000 | 2,000,000
Fair Value |  |
Less than Twelve Months | $ 4 | $ 0
Twelve Months or Longer | 16 | 17
Total | 20 | 17
Unrealized Loss |  |
Less than Twelve Months | 0 | 0
Twelve Months or Longer | 1 | 1
Total | $ 1 | $ 1
Debt Securities | Foreign Notes |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 1,000,000 | 1,000,000
Fair Value |  |
Less than Twelve Months | $ 0 | $ 0
Twelve Months or Longer | 10 | 10
Total | 10 | 10
Unrealized Loss |  |
Less than Twelve Months | 0 | 0
Twelve Months or Longer | 0 | 0
Total | $ 0 | $ 0
Debt Securities | Municipal bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Number of Debt Securities | security | 1,000,000 | 1,000,000
Fair Value |  |
Less than Twelve Months | $ 0 | $ 0
Twelve Months or Longer | 5 | 5
Total | 5 | 5
Unrealized Loss |  |
Less than Twelve Months | 0 | 0
Twelve Months or Longer | 0 | 0
Total | $ 0 | $ 0

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