Regulatory Ratios and Capital - Schedule of Compliance With Regulatory Capital Requirements (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	0.0600
Capital Required to be Well Capitalized to Risk Weighted Assets	0.1000
CET1, actual amount	$ 3,445,091	$ 3,394,471
Tier One Risk Based Capital	3,855,091	3,804,471
Capital	4,188,462	4,509,943
Tier One Leverage Capital	$ 3,855,091	$ 3,804,471
CET1, actual ratio	12.07%	12.13%
Tier One Risk Based Capital to Risk Weighted Assets	0.1351	0.1360
Capital to Risk Weighted Assets	0.1468	0.1612
Tier One Leverage Capital to Average Assets	0.1165	0.1165
Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 to be well capitalized under prompt corrective action provisions, ratio	6.50%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	0.0800
Capital Required to be Well Capitalized to Risk Weighted Assets	0.1000
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	0.0500
CET1, actual amount	$ 3,504,224	$ 3,618,691
Tier One Risk Based Capital	3,504,224	3,618,691
Capital	3,837,595	3,951,503
Tier One Leverage Capital	$ 3,504,224	$ 3,618,691
CET1, actual ratio	12.35%	13.01%
Tier One Risk Based Capital to Risk Weighted Assets	0.1235	0.1301
Capital to Risk Weighted Assets	0.1353	0.1420
Tier One Leverage Capital to Average Assets	0.1067	0.1118
Basel III, Phase-In Schedule
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 for capital adequacy purposes, ratio	7.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	0.0850
Capital Required for Capital Adequacy to Risk Weighted Assets	0.1050
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	0.0400
Basel III, Phase-In Schedule \| Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
CET1 for capital adequacy purposes, ratio	7.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	0.0850
Capital Required for Capital Adequacy to Risk Weighted Assets	0.1050
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	0.0400

Common Equity Tier 1 Capital

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Common Equity Tier 1, Capital to Risk Weighted Assets

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Amount of total capital as defined by regulatory framework.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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