Derivative and Hedging Activities and Restricted Cash - Narrative (Details) - USD ($)	Mar. 31, 2025	Dec. 31, 2024
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains on derivatives	$ 40,000,000	$ 47,000,000
Amount of gain (loss), net of tax, to be reclassified during the next 12 months	28,000,000
Interest rate swaps on FHLB advances \| Derivatives designated as hedging instruments: \| Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	$ 0

Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-11

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4E
-Publisher FASB
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Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Subparagraph (d)
-Publisher FASB
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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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