Allowance for Credit Losses (Summary of Loans Restructured and Subsequently Defaulted Under the Restructured Terms) (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($) contract	Mar. 31, 2022 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	13	57
TDRs, balance \| $	$ 3,097	$ 14,839
Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	14
TDRs, balance \| $	$ 6,793
Commercial, industrial and other \| Commercial, industrial and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	3	17
TDRs, balance \| $	$ 282	$ 5,205
Commercial, industrial and other \| Commercial, industrial and other \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	11
TDRs, balance \| $	$ 4,526
Commercial real estate \| Non-construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	2	5
TDRs, balance \| $	$ 1,907	$ 4,613
Commercial real estate \| Non-construction \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	2
TDRs, balance \| $	$ 2,163
Residential real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	8	35
TDRs, balance \| $	$ 908	$ 5,021
Residential real estate \| Payments in Default
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count \| contract	1
TDRs, balance \| $	$ 104

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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