Loans and Allowance For Credit Losses Loans (Schedule of Restructured Trouble Debt Restructuring By Class) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) contract	Sep. 30, 2020 USD ($) contract	Sep. 30, 2021 USD ($) contract	Sep. 30, 2020 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	2	0	3
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 447	$ 0	$ 808
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 447	$ 0	$ 808
Commercial real estate owner occupied other [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract			0	1
Financing Receivable, Troubled Debt Restructuring, Premodification			$ 0	$ 361
Financing Receivable, Troubled Debt Restructuring, Postmodification			$ 0	$ 361
Residential 1-4 family real estate personal residence [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	1	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 48	$ 0	$ 48
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 48	$ 0	$ 48
Residential 1-4 family real estate rental - small loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	1	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 399	$ 0	$ 399
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 399	$ 0	$ 399

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

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 http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

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

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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