Loans Receivable - Modified TDRs (Details) - Troubled Debt Restructured Loans	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	53	36	35
Outstanding Principal Balance	$ 22,495,000	$ 19,200,000	$ 13,438,000
Commercial business
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	38	26	23
Outstanding Principal Balance	$ 21,594,000	$ 18,152,000	$ 10,088,000
Commercial business \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	31	19	19
Outstanding Principal Balance	$ 16,129,000	$ 7,212,000	$ 7,398,000
Commercial business \| Owner-occupied commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	4	3	2
Outstanding Principal Balance	$ 2,521,000	$ 1,366,000	$ 569,000
Commercial business \| Non-owner occupied commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3	4	2
Outstanding Principal Balance	$ 2,944,000	$ 9,574,000	$ 2,121,000
Real estate construction and land development
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	2	6
Outstanding Principal Balance	$ 665,000	$ 938,000	$ 3,284,000
Real estate construction and land development \| One-to-four family residential
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	2	5
Outstanding Principal Balance	$ 665,000	$ 938,000	$ 2,206,000
Initial advance at the time of modification	$ 0	$ 0	$ 0
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	1
Outstanding Principal Balance	$ 0	$ 0	$ 1,078,000
Consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	13	8	6
Outstanding Principal Balance	$ 236,000	$ 110,000	$ 66,000

Loans and Leases Receivable, Impaired by Modification, Initial Loan Disbursement on construction-type loans.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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