Derivative Instruments and Hedging Activities (Notional and Recorded Fair Values) (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Notional amount	$ 24,498,000,000	$ 22,610,000,000
Derivative asset, fair value	386,000,000	219,000,000
Derivative liability, fair value	451,000,000	51,000,000
Net credit valuation adjustment reducing fair value	13,000,000	3,000,000
Other assets
Derivative [Line Items]
Derivative asset, fair value	386,000,000	219,000,000
Other liabilities
Derivative [Line Items]
Derivative liability, fair value	451,000,000	51,000,000
Derivatives designated as hedging instruments
Derivative [Line Items]
Notional amount	9,361,000,000	7,862,000,000
Derivatives designated as hedging instruments | Other assets
Derivative [Line Items]
Derivative asset, fair value	84,000,000	10,000,000
Derivatives designated as hedging instruments | Other liabilities
Derivative [Line Items]
Derivative liability, fair value	1,000,000	0
Derivatives designated as hedging instruments | Purchased interest rate floors | Cash Flow Hedging
Derivative [Line Items]
Notional amount	0	0
Derivatives designated as hedging instruments | Purchased interest rate floors | Other assets | Cash Flow Hedging
Derivative [Line Items]
Derivative asset, fair value	0	0
Derivatives designated as hedging instruments | Purchased interest rate floors | Other liabilities | Cash Flow Hedging
Derivative [Line Items]
Derivative liability, fair value	0	0
Derivatives designated as hedging instruments | Interest rate swaps | Cash Flow Hedging
Derivative [Line Items]
Notional amount	7,633,000,000	6,883,000,000
Derivatives designated as hedging instruments | Interest rate swaps | Fair Value Hedging
Derivative [Line Items]
Notional amount	500,000,000	500,000,000
Derivatives designated as hedging instruments | Interest rate swaps | Other assets | Cash Flow Hedging
Derivative [Line Items]
Derivative asset, fair value	0	0
Derivatives designated as hedging instruments | Interest rate swaps | Other assets | Fair Value Hedging
Derivative [Line Items]
Derivative asset, fair value	0	0
Derivatives designated as hedging instruments | Interest rate swaps | Other liabilities | Cash Flow Hedging
Derivative [Line Items]
Derivative liability, fair value	1,000,000	0
Derivatives designated as hedging instruments | Interest rate swaps | Other liabilities | Fair Value Hedging
Derivative [Line Items]
Derivative liability, fair value	0	0
Derivatives designated as hedging instruments | Asset hedges: Pay-fixed interest rate swaps 1 | Fair Value Hedging
Derivative [Line Items]
Notional amount	1,228,000,000	479,000,000
Derivatives designated as hedging instruments | Asset hedges: Pay-fixed interest rate swaps 1 | Other assets | Fair Value Hedging
Derivative [Line Items]
Derivative asset, fair value	84,000,000	10,000,000
Derivatives designated as hedging instruments | Asset hedges: Pay-fixed interest rate swaps 1 | Other liabilities | Fair Value Hedging
Derivative [Line Items]
Derivative liability, fair value	0	0
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional amount	15,137,000,000	14,748,000,000
Derivatives not designated as hedging instruments | Other assets
Derivative [Line Items]
Derivative asset, fair value	302,000,000	209,000,000
Derivatives not designated as hedging instruments | Other liabilities
Derivative [Line Items]
Derivative liability, fair value	450,000,000	51,000,000
Derivatives not designated as hedging instruments | Customer interest rate derivatives
Derivative [Line Items]
Notional amount	13,670,000,000	13,174,000,000
Derivatives not designated as hedging instruments | Customer interest rate derivatives | Other assets
Derivative [Line Items]
Derivative asset, fair value	296,000,000	200,000,000
Derivatives not designated as hedging instruments | Customer interest rate derivatives | Other liabilities
Derivative [Line Items]
Derivative liability, fair value	443,000,000	48,000,000
Derivatives not designated as hedging instruments | Other interest rate derivatives
Derivative [Line Items]
Notional amount	862,000,000	1,286,000,000
Derivatives not designated as hedging instruments | Other interest rate derivatives | Other assets
Derivative [Line Items]
Derivative asset, fair value	0	6,000,000
Derivatives not designated as hedging instruments | Other interest rate derivatives | Other liabilities
Derivative [Line Items]
Derivative liability, fair value	0	1,000,000
Derivatives not designated as hedging instruments | Foreign exchange derivatives
Derivative [Line Items]
Notional amount	605,000,000	288,000,000
Derivatives not designated as hedging instruments | Foreign exchange derivatives | Other assets
Derivative [Line Items]
Derivative asset, fair value	6,000,000	3,000,000
Derivatives not designated as hedging instruments | Foreign exchange derivatives | Other liabilities
Derivative [Line Items]
Derivative liability, fair value	$ 7,000,000	$ 2,000,000