Regulatory Capital and Restrictions - Schedule of Information on Capital Ratios (Details) $ in Thousands	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual, CET1 Risk-Based Capital	$ 6,826,758	$ 6,441,440
Actual, Tier 1 Risk-Based Capital	7,110,737	6,725,419
Actual, Total Risk-Based Capital	8,254,693	7,861,688
Actual, Tier 1 Leverage Capital	$ 7,110,737	$ 6,725,419
Ratio, CET1 Risk-Based Capital	0.1171	0.1120
Actual, Ratio, Tier 1 Risk-Based Capital	0.1220	0.1169
Ratio, Total Risk-Based Capital	0.1416	0.1367
Actual, Ratio, Tier 1 Leverage Capital	0.0848	0.0833
Minimum Requirement, CET1 Risk-Based Capital	$ 2,623,056	$ 2,588,039
Minimum Requirement, Tier 1 Risk-Based Capital	3,497,408	3,450,719
Minimum Requirement, Total Risk-Based Capital	4,663,211	4,600,959
Minimum Requirement, Tier 1, Leverage Capital	$ 3,353,890	$ 3,230,039
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	$ 3,788,859	$ 3,738,279
Well Capitalized, Tier 1 Risk-Based Capital	4,663,211	4,600,959
Well Capitalized, Total Risk-Based Capital	5,829,014	5,751,199
Well Capitalized, Tier 1 Leverage Capital	$ 4,192,362	$ 4,037,549
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
Subsidiaries
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Actual, CET1 Risk-Based Capital	$ 7,134,807	$ 7,007,352
Actual, Tier 1 Risk-Based Capital	7,134,807	7,007,352
Actual, Total Risk-Based Capital	7,855,305	7,720,373
Actual, Tier 1 Leverage Capital	$ 7,134,807	$ 7,007,352
Ratio, CET1 Risk-Based Capital	0.1223	0.1219
Actual, Ratio, Tier 1 Risk-Based Capital	0.1223	0.1219
Ratio, Total Risk-Based Capital	0.1347	0.1343
Actual, Ratio, Tier 1 Leverage Capital	0.0851	0.0869
Minimum Requirement, CET1 Risk-Based Capital	$ 2,625,165	$ 2,586,346
Minimum Requirement, Tier 1 Risk-Based Capital	3,500,220	3,448,461
Minimum Requirement, Total Risk-Based Capital	4,666,959	4,597,948
Minimum Requirement, Tier 1, Leverage Capital	$ 3,351,691	$ 3,226,561
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	$ 3,791,905	$ 3,735,833
Well Capitalized, Tier 1 Risk-Based Capital	4,666,959	4,597,948
Well Capitalized, Total Risk-Based Capital	5,833,699	5,747,435
Well Capitalized, Tier 1 Leverage Capital	$ 4,189,614	$ 4,033,202
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

Amount of total capital as defined by regulatory framework.

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