Derivative Financial Instruments - Exposure to Credit Loss on Call Options Held (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Fair Value	$ 952	$ 546
Not Designated as Hedging Instrument \| Call options
Derivatives, Fair Value [Line Items]
Notional Amount	25,372	23,297
Fair Value	648	244
Collateral	579	219
Net Credit Risk	81	33
Not Designated as Hedging Instrument \| Call options \| Merrill Lynch
Derivatives, Fair Value [Line Items]
Notional Amount	4,033	3,563
Fair Value	69	23
Collateral	26	0
Net Credit Risk	43	23
Not Designated as Hedging Instrument \| Call options \| Morgan Stanley
Derivatives, Fair Value [Line Items]
Notional Amount	2,375	1,699
Fair Value	50	14
Collateral	60	19
Net Credit Risk	0	0
Not Designated as Hedging Instrument \| Call options \| Barclay's Bank
Derivatives, Fair Value [Line Items]
Notional Amount	6,137	6,049
Fair Value	121	65
Collateral	113	59
Net Credit Risk	8	6
Not Designated as Hedging Instrument \| Call options \| Canadian Imperial Bank of Commerce
Derivatives, Fair Value [Line Items]
Notional Amount	6,542	5,169
Fair Value	204	68
Collateral	180	64
Net Credit Risk	24	4
Not Designated as Hedging Instrument \| Call options \| Wells Fargo
Derivatives, Fair Value [Line Items]
Notional Amount	1,480	1,361
Fair Value	54	17
Collateral	53	17
Net Credit Risk	1	0
Not Designated as Hedging Instrument \| Call options \| Goldman Sachs
Derivatives, Fair Value [Line Items]
Notional Amount	1,212	1,133
Fair Value	23	9
Collateral	22	10
Net Credit Risk	1	0
Not Designated as Hedging Instrument \| Call options \| Credit Suisse
Derivatives, Fair Value [Line Items]
Notional Amount	266	1,039
Fair Value	9	5
Collateral	9	5
Net Credit Risk	0	0
Not Designated as Hedging Instrument \| Call options \| Truist
Derivatives, Fair Value [Line Items]
Notional Amount	2,055	2,489
Fair Value	89	35
Collateral	85	36
Net Credit Risk	4	0
Not Designated as Hedging Instrument \| Call options \| Citibank
Derivatives, Fair Value [Line Items]
Notional Amount	1,272	795
Fair Value	29	8
Collateral	31	9
Net Credit Risk	$ 0	$ 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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