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Derivatives - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	$ 12,363,000,000	$ 10,755,000,000
Derivative, Collateral, Right to Reclaim Cash	25,000,000	1,000,000
Cash collateral held	49,000,000	56,000,000
Securities collateral held or repledged	0	1,000,000
Collateral Securities Repledged, Delivered, or Used	0	0
Collateral Pledged
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Collateral, Right to Reclaim Cash	16,000,000	16,000,000
Asset Pledged as Collateral
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Security Not Offset	14,000,000	8,000,000
Asset Pledged as Collateral \| Over the Counter [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Security Not Offset	112,000,000	57,000,000
Reclassification out of Accumulated Other Comprehensive Income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net reclassifications from AOCI to earnings resulting from the discontinuance of cash-flow hedges due to forecasted transactions that were no longer probable of occurring	0	0	$ 0
Accumulated Other Comprehensive Income (Loss) ("AOCI"), net of tax
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Deferred net gains on derivative instruments recorded in AOCI that are expected to be reclassified to earnings during the next twelve months	18,000,000
Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	8,269,000,000	8,032,000,000
Interest rate swaps \| Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	6,600,000,000	6,600,000,000
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	$ 500,000,000	$ 500,000,000