Derivative Financial Instruments - Exposure to Credit Loss on Call Options Held (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Fair Value	$ 717	$ 546
Not Designated as Hedging Instrument \| Call options
Derivatives, Fair Value [Line Items]
Notional Amount	24,348	23,297
Fair Value	432	244
Collateral	351	219
Net Credit Risk	83	33
Not Designated as Hedging Instrument \| Call options \| Merrill Lynch
Derivatives, Fair Value [Line Items]
Notional Amount	3,834	3,563
Fair Value	44	23
Collateral	0	0
Net Credit Risk	44	23
Not Designated as Hedging Instrument \| Call options \| Morgan Stanley
Derivatives, Fair Value [Line Items]
Notional Amount	2,038	1,699
Fair Value	22	14
Collateral	24	19
Net Credit Risk	0	0
Not Designated as Hedging Instrument \| Call options \| Barclay's Bank
Derivatives, Fair Value [Line Items]
Notional Amount	5,939	6,049
Fair Value	106	65
Collateral	95	59
Net Credit Risk	11	6
Not Designated as Hedging Instrument \| Call options \| Canadian Imperial Bank of Commerce
Derivatives, Fair Value [Line Items]
Notional Amount	6,006	5,169
Fair Value	129	68
Collateral	113	64
Net Credit Risk	16	4
Not Designated as Hedging Instrument \| Call options \| Wells Fargo
Derivatives, Fair Value [Line Items]
Notional Amount	1,270	1,361
Fair Value	31	17
Collateral	29	17
Net Credit Risk	2	0
Not Designated as Hedging Instrument \| Call options \| Goldman Sachs
Derivatives, Fair Value [Line Items]
Notional Amount	1,178	1,133
Fair Value	16	9
Collateral	14	10
Net Credit Risk	2	0
Not Designated as Hedging Instrument \| Call options \| Credit Suisse
Derivatives, Fair Value [Line Items]
Notional Amount	672	1,039
Fair Value	7	5
Collateral	7	5
Net Credit Risk	0	0
Not Designated as Hedging Instrument \| Call options \| Truist
Derivatives, Fair Value [Line Items]
Notional Amount	2,204	2,489
Fair Value	60	35
Collateral	54	36
Net Credit Risk	6	0
Not Designated as Hedging Instrument \| Call options \| Citibank
Derivatives, Fair Value [Line Items]
Notional Amount	1,207	795
Fair Value	17	8
Collateral	15	9
Net Credit Risk	$ 2	$ 0

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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Nominal or face amount used to calculate payment on derivative.

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