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Derivatives - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	$ 6,757		$ 7,081
Derivative, Collateral, Right to Reclaim Cash	23		31
Cash collateral held	62		78
Securities Received as Collateral	0		0
Collateral Pledged
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Collateral, Right to Reclaim Cash	12		10
Asset Pledged as Collateral [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Collateral, Right to Reclaim Securities	5		1
Asset Pledged as Collateral [Member] \| Over the Counter [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Collateral, Right to Reclaim Securities	107		103
Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring	0	$ 0
AOCI Attributable to Parent [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	24
Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	1,926		2,210
Interest rate swaps \| Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	333		$ 344
SOFR Plus Two Point One Two Five Percent Plus Zero Point Two Six One Six One Percent Junior Subordinated Notes Due Two Thousand Sixty Seven
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Junior Subordinated Debentures	$ 500