Loans Receivable - TDRs Subsequently Defaulted (Details) - Troubled Debt Restructured Loans $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	8	5	3
Recorded Investment \| $	$ 2,620	$ 1,308	$ 1,631
Commercial business
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	6	2	1
Recorded Investment \| $	$ 1,955	$ 363	$ 488
Commercial business \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	5	1	0
Recorded Investment \| $	$ 1,890	$ 283	$ 0
Commercial business \| Owner-occupied commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	1	1
Recorded Investment \| $	$ 65	$ 80	$ 488
Real estate construction and land development
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	2	2
Recorded Investment \| $	$ 665	$ 938	$ 1,143
Real estate construction and land development \| One-to-four family residential
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	2	2
Recorded Investment \| $	$ 665	$ 938	$ 1,143
Consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	0	1	0
Recorded Investment \| $	$ 0	$ 7	$ 0

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- Definition

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://www.xbrl.org/2003/role/presentationRef
-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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- Definition

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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