Capital Ratios (Narrative) (Details) $ in Billions	6 Months Ended	12 Months Ended
Jun. 30, 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	15.02	14.07
Tier One Leverage Capital to Average Assets	8.46	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	8.28%
Total Risk-based Capital Ratio: Ratio	16.28	15.33

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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