Derivative Instruments and Hedging Activities (Fair Value Amounts of Derivative Instruments Reported on our Condensed Consolidated Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
receivable position	$ 33	$ 23
payable position	17	42
Notional amount	44,468	33,833
Credit derivative, maximum exposure, undiscounted	29	82
Total derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	31	22
payable position	6	1
Notional amount	42,251	33,570
Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	2	1
payable position	11	41
Notional amount	2,217	263
Interest rate contracts | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	2	0
payable position	0	0
Notional amount	2,158	116
Swaps | Total derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	0	0
Notional amount	35,835	30,619
Swaps | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	0	0
Notional amount	2,000	0
Purchased options | Total derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	31	22
payable position	0	0
Notional amount	6,250	2,800
Forwards | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	0	0
Notional amount	70	37
Written options | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	2	0
payable position	0	0
Notional amount	88	79
Foreign exchange contracts | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	1	1
Notional amount	59	147
Forwards | Total derivatives designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	6	1
Notional amount	166	151
Forwards | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	1	1
Notional amount	59	147
Other credit derivatives | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	10	39
Equity contracts | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	1
payable position	0	1
Notional amount	0	0
Written options | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	0
payable position	0	1
Notional amount	0	0
Purchased options | Total derivatives not designated as accounting hedges
Derivatives, Fair Value [Line Items]
receivable position	0	1
payable position	0	0
Notional amount	$ 0	$ 0