Loans and Allowance for Credit Losses Loans (Schedule of Restructured Trouble Debt Restructuring By Class) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($) contract	Dec. 31, 2019 USD ($) contract
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	3	13
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 808	$ 1,074
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 808	$ 1,074
Commercial real estate owner occupied other
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 361	$ 325
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 361	$ 325
Multifamily
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 35
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 35
Commercial real estate non-owner occupied retail
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	2
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 162
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 162
Commercial real estate non-owner occupied other
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 126
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 126
Residential 1-4 family real estate personal residence
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	3
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 48	$ 151
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 48	$ 151
Residential 1-4 family real estate rental - small loan
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	1	4
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 399	$ 259
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 399	$ 259
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts \| contract	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 16
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 16

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

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