Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) loan	Sep. 30, 2018 USD ($) loan	Sep. 30, 2019 USD ($) loan	Sep. 30, 2018 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 195	$ 219	$ 456	$ 578
Post-Modification Recorded Balance	$ 185	$ 205	$ 439	$ 576
Number of Loans \| loan	3	5	8	15
Residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance	$ 195	$ 154	$ 456	$ 490
Post-Modification Recorded Balance	$ 185	$ 140	$ 439	$ 487
Number of Loans \| loan	3	4	8	11
Home equity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance		$ 65		$ 81
Post-Modification Recorded Balance		$ 65		$ 81
Number of Loans \| loan		1		3
Individuals' loans for household and other personal expenditures
Financing Receivable, Troubled Debt Restructuring [Line Items]
Pre-Modification Recorded Balance				$ 7
Post-Modification Recorded Balance				$ 8
Number of Loans \| loan				1

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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=118936363&loc=SL6953676-111524

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

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- Definition

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

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