Derivative Instruments and Hedging Activities (Notional and Recorded Fair Values) (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Derivative [Line Items]
Notional amount	$ 24,360,000,000	$ 22,610,000,000
Other assets	295,000,000	219,000,000
Other liabilities	491,000,000	51,000,000
Net credit valuation adjustment reducing fair value	17,000,000	3,000,000
Other assets
Derivative [Line Items]
Other assets	592,000,000	249,000,000
Other liabilities
Derivative [Line Items]
Other liabilities	491,000,000	236,000,000
Derivatives designated as hedges
Derivative [Line Items]
Notional amount	9,161,000,000	7,862,000,000
Derivatives designated as hedges | Other assets
Derivative [Line Items]
Other assets	83,000,000	10,000,000
Derivatives designated as hedges | Other liabilities
Derivative [Line Items]
Other liabilities	2,000,000	0
Derivatives designated as hedges | Interest rate swaps | Cash Flow Hedging
Derivative [Line Items]
Notional amount	7,433,000,000	6,883,000,000
Derivatives designated as hedges | Interest rate swaps | Fair Value Hedging
Derivative [Line Items]
Notional amount	500,000,000	500,000,000
Derivatives designated as hedges | Interest rate swaps | Other assets | Cash Flow Hedging
Derivative [Line Items]
Other assets	0	0
Derivatives designated as hedges | Interest rate swaps | Other assets | Fair Value Hedging
Derivative [Line Items]
Other assets	0	0
Derivatives designated as hedges | Interest rate swaps | Other liabilities | Cash Flow Hedging
Derivative [Line Items]
Other liabilities	2,000,000	0
Derivatives designated as hedges | Interest rate swaps | Other liabilities | Fair Value Hedging
Derivative [Line Items]
Other liabilities	0	0
Derivatives designated as hedges | Asset hedges: Pay-fixed interest rate swaps | Fair Value Hedging
Derivative [Line Items]
Notional amount	1,228,000,000	479,000,000
Derivatives designated as hedges | Asset hedges: Pay-fixed interest rate swaps | Other assets | Fair Value Hedging
Derivative [Line Items]
Other assets	83,000,000	10,000,000
Derivatives designated as hedges | Asset hedges: Pay-fixed interest rate swaps | Other liabilities | Fair Value Hedging
Derivative [Line Items]
Other liabilities	0	0
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional amount	15,199,000,000	14,748,000,000
Derivatives not designated as hedging instruments | Other assets
Derivative [Line Items]
Other assets	509,000,000	239,000,000
Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Other liabilities	489,000,000	236,000,000
Derivatives not designated as hedging instruments | Customer-facing interest rate derivatives
Derivative [Line Items]
Notional amount	6,931,000,000	6,587,000,000
Derivatives not designated as hedging instruments | Customer-facing interest rate derivatives | Other assets
Derivative [Line Items]
Other assets	1,000,000	192,000,000
Derivatives not designated as hedging instruments | Customer-facing interest rate derivatives | Other liabilities
Derivative [Line Items]
Other liabilities	483,000,000	36,000,000
Derivatives not designated as hedging instruments | Offsetting interest rate derivatives
Derivative [Line Items]
Notional amount	6,931,000,000	6,587,000,000
Derivatives not designated as hedging instruments | Offsetting interest rate derivatives | Other assets
Derivative [Line Items]
Other assets	501,000,000	38,000,000
Derivatives not designated as hedging instruments | Offsetting interest rate derivatives | Other assets | Fair Value Hedging
Derivative [Line Items]
Other assets	204,000,000	8,000,000
Derivatives not designated as hedging instruments | Offsetting interest rate derivatives | Other liabilities
Derivative [Line Items]
Other liabilities	1,000,000	197,000,000
Derivatives not designated as hedging instruments | Offsetting interest rate derivatives | Other liabilities | Fair Value Hedging
Derivative [Line Items]
Other liabilities	1,000,000	12,000,000
Derivatives not designated as hedging instruments | Other interest rate derivatives
Derivative [Line Items]
Notional amount	905,000,000	1,286,000,000
Derivatives not designated as hedging instruments | Other interest rate derivatives | Other assets
Derivative [Line Items]
Other assets	1,000,000	6,000,000
Derivatives not designated as hedging instruments | Other interest rate derivatives | Other liabilities
Derivative [Line Items]
Other liabilities	0	1,000,000
Derivatives not designated as hedging instruments | Foreign exchange derivatives
Derivative [Line Items]
Notional amount	432,000,000	288,000,000
Derivatives not designated as hedging instruments | Foreign exchange derivatives | Other assets
Derivative [Line Items]
Other assets	6,000,000	3,000,000
Derivatives not designated as hedging instruments | Foreign exchange derivatives | Other liabilities
Derivative [Line Items]
Other liabilities	$ 5,000,000	$ 2,000,000