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Regulatory Capital and Restrictions - Schedule of Information on Capital Ratios (Detail) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Actual, CET1 Risk-Based Capital | $ 6,318,876 | $ 6,188,433
Actual, Tier 1 Risk-Based Capital | 6,602,855 | 6,472,412
Actual, Total Risk-Based Capital | 7,800,717 | 7,643,423
Actual, Tier 1 Leverage Capital | $ 6,602,855 | $ 6,472,412
Ratio, CET1 Risk-Based Capital | 0.1154 | 0.1111
Actual, Ratio, Tier 1 Risk-Based Capital | 0.1206 | 0.1162
Ratio, Total Risk-Based Capital | 0.1424 | 0.1372
Actual, Ratio, Tier 1 Leverage Capital | 0.0870 | 0.0906
Minimum Requirement, CET1 Risk-Based Capital | $ 2,464,542 | $ 2,507,190
Minimum Requirement, Tier 1 Risk-Based Capital | 3,286,057 | 3,342,920
Minimum Requirement, Total Risk-Based Capital | 4,381,409 | 4,457,227
Minimum Requirement, Tier 1, Leverage Capital | $ 3,034,369 | $ 2,857,890
Minimum Requirement, Ratio, Tier 1 Risk-Based Capital | 0.060 | 0.060
Minimum Requirement, Ratio, Total Risk-Based Capital | 0.080 | 0.080
Minimum Requirement, Ratio, Tier 1 Leverage Capital | 0.040 | 0.040
Well Capitalized, CET1 Risk-Based Capital | $ 3,559,895 | $ 3,621,497
Well Capitalized, Tier 1 Risk-Based Capital | 4,381,409 | 4,457,227
Well Capitalized, Total Risk-Based Capital | 5,476,761 | 5,571,534
Well Capitalized, Tier 1 Leverage Capital | $ 3,792,961 | $ 3,572,362
Well Capitalized, Ratio, Tier 1 Risk-Based Capital | 0.080 | 0.080
Well Capitalized, Ratio, Total Risk-Based Capital | 0.100 | 0.100
Well Capitalized, Ratio, Tier 1 Leverage Capital | 0.050 | 0.050
Transition regulatory capital percentage | 25.00% | 50.00%
Subsidiaries |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Actual, CET1 Risk-Based Capital | $ 6,847,474 | $ 6,913,443
Actual, Tier 1 Risk-Based Capital | 6,847,474 | 6,913,443
Actual, Total Risk-Based Capital | 7,512,143 | 7,494,332
Actual, Tier 1 Leverage Capital | $ 6,847,474 | $ 6,913,443
Ratio, CET1 Risk-Based Capital | 0.1253 | 0.1243
Actual, Ratio, Tier 1 Risk-Based Capital | 0.1253 | 0.1243
Ratio, Total Risk-Based Capital | 0.1374 | 0.1347
Actual, Ratio, Tier 1 Leverage Capital | 0.0904 | 0.0969
Minimum Requirement, CET1 Risk-Based Capital | $ 2,460,031 | $ 2,502,835
Minimum Requirement, Tier 1 Risk-Based Capital | 3,280,042 | 3,337,113
Minimum Requirement, Total Risk-Based Capital | 4,373,389 | 4,449,484
Minimum Requirement, Tier 1, Leverage Capital | $ 3,031,190 | $ 2,855,212
Minimum Requirement, Ratio, Tier 1 Risk-Based Capital | 0.060 | 0.060
Minimum Requirement, Ratio, Total Risk-Based Capital | 0.080 | 0.080
Minimum Requirement, Ratio, Tier 1 Leverage Capital | 0.040 | 0.040
Well Capitalized, CET1 Risk-Based Capital | $ 3,553,378 | $ 3,615,206
Well Capitalized, Tier 1 Risk-Based Capital | 4,373,389 | 4,449,484
Well Capitalized, Total Risk-Based Capital | 5,466,736 | 5,561,855
Well Capitalized, Tier 1 Leverage Capital | $ 3,788,988 | $ 3,569,015
Well Capitalized, Ratio, Tier 1 Risk-Based Capital | 0.080 | 0.080
Well Capitalized, Ratio, Total Risk-Based Capital | 0.100 | 0.100
Well Capitalized, Ratio, Tier 1 Leverage Capital | 0.050 | 0.050
Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Ratio, CET1 Risk-Based Capital | 0.045 | 0.045
Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets | Subsidiaries |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Ratio, CET1 Risk-Based Capital | 0.045 | 0.045
Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Ratio, CET1 Risk-Based Capital | 0.065 | 0.065
Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | Subsidiaries |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Ratio, CET1 Risk-Based Capital | 0.065 | 0.065

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