Loans Receivable - TDRs Subsequently Defaulted (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) contract	Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance	$ 2,143	$ 4,170
Commercial business
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance	1,944	3,955
Commercial business \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance	1,372	2,607
Commercial business \| Owner-occupied commercial real estate
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance	426	1,142
Real estate construction and land development
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance	0	0
Real estate construction and land development \| One-to-four family residential
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance	0	0
Consumer
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance	$ 143	$ 139
Troubled Debt Restructured Loans
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	17	8	5
Recorded Investment	$ 14,050	$ 2,620	$ 1,308
Troubled Debt Restructured Loans \| Commercial business
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	17	6	2
Recorded Investment	$ 14,050	$ 1,955	$ 363
Troubled Debt Restructured Loans \| Commercial business \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	13	5	1
Recorded Investment	$ 12,856	$ 1,890	$ 283
Troubled Debt Restructured Loans \| Commercial business \| Owner-occupied commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3	1	1
Recorded Investment	$ 1,142	$ 65	$ 80
Troubled Debt Restructured Loans \| Real estate construction and land development
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	2	2
Recorded Investment	$ 0	$ 665	$ 938
Troubled Debt Restructured Loans \| Real estate construction and land development \| One-to-four family residential
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	2	2
Recorded Investment	$ 0	$ 665	$ 938
Troubled Debt Restructured Loans \| Real estate construction and land development \| Five or more family residential and commercial properties
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	0
Recorded Investment	$ 0	$ 0	$ 0
Troubled Debt Restructured Loans \| Consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	0	1
Recorded Investment	$ 0	$ 0	$ 7
30-89 Days \| Troubled Debt Restructured Loans
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract			4
Modified subsequently \| Troubled Debt Restructured Loans
Financing Receivable, Modifications [Line Items]
Related Specific Valuation Allowance		$ 260	$ 1

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
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