Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Mortgage loan interest rate lock commitments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative financial instruments, Notional	$ 25,139	$ 15,430
Derivative financial instruments, Balance Sheet Location, description	Other assets	Other assets
Derivative financial instruments, Fair Value, Asset/(Liability)	$ 384	$ 196
MBS forward sales commitments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative financial instruments, Notional	$ 19,000	$ 10,750
Derivative financial instruments, Balance Sheet Location, description	Other liabilities	Other liabilities
Derivative financial instruments, Fair Value, Asset/(Liability)	$ (88)	$ (28)
Total derivative financial instruments [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative financial instruments, Notional	44,139	26,180
Derivative financial instruments, Fair Value, Asset/(Liability)	$ 296	$ 168

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Description of balance sheet location.

+ References

No definition available.

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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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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