Loans and Allowance for Loan Losses Schedule of Troubled Debt Restructured Loans (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($) loans	Mar. 31, 2020 USD ($) loans	Mar. 31, 2019 USD ($) loans	Dec. 31, 2019 USD ($)
Loans and Allowance for Loan Losses [Abstract]
Loans, modifications	$ 0		$ 0		$ 4
Troubled debt restructured loans included in nonaccrual	0		0		$ 4
Loans, modifications, number of contracts \| loans		0
Loans, modifications, pre-modification recorded investment	0	$ 0
Loans, modifications, post-modification recorded investment	$ 0	$ 0
Loans, modifications, subsequent default, recorded investment			$ 0	$ 537
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts \| loans			0	1

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

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

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

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Amount of financing receivable modified as troubled debt restructuring.

+ 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=118936363&loc=SL6953676-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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Note 7. Impaired Loans and Allowance for Loan Losses [Abstract]

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Amount of troubled debt restructured loans included in the nonaccrual category

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