Capital Ratios (Narrative) (Details) $ in Billions	3 Months Ended	12 Months Ended
	Mar. 31, 2021 USD ($)	Dec. 31, 2020
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Debt Instrument, Redemption Period	5 years
Capital Ratios, Basel III, Capital Conservation Buffer, Year Three	2.50%
Community Bank Leverage Ratio, Minimum		9.00%
Paycheck Protection Program, Risk-Weight For Risk-Based Capital Rules	0.00%
Consolidated asset limit on small bank holding companies	$ 3
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 Risk-based Capital Ratio: Ratio	14.63	14.07
Tier One Leverage Capital to Average Assets	8.65	8.54
Common Equity Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	6.50%
Tier 1 Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	8.00
Tier 1 Leverage Ratio: Well Capitalized Minimum: Ratio	5.00
Total Risk-based Capital Ratio: Well Capitalized Minimum: Ratio	10.00
Capital ratios, capital conservation buffer	7.89%
Total Risk-based Capital Ratio: Ratio	15.89	15.33