Derivative Financial Instruments - Notional amounts and fair values of derivative financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivative Financial Instruments
Notional Amount	$ 74,363	$ 66,566
Asset (Liability) Fair Value	90	74
Interest rate lock commitments
Derivative Financial Instruments
Notional Amount	34,203	33,406
Asset (Liability) Fair Value	289	270
Interest rate lock commitments \| Other Assets
Derivative Financial Instruments
Notional Amount	29,072	27,188
Asset (Liability) Fair Value	330	310
Interest rate lock commitments \| Other Liabilities
Derivative Financial Instruments
Notional Amount	5,131	6,218
Asset (Liability) Fair Value	(41)	(40)
Forward Commitments
Derivative Financial Instruments
Notional Amount	33,500	26,500
Asset (Liability) Fair Value	(168)	(176)
Forward Commitments \| Other Assets
Derivative Financial Instruments
Notional Amount	2,000
Asset (Liability) Fair Value	2
Forward Commitments \| Other Liabilities
Derivative Financial Instruments
Notional Amount	31,500	26,500
Asset (Liability) Fair Value	(170)	(176)
Customer derivatives - Interest rate swaps
Derivative Financial Instruments
Notional Amount	6,660	6,660
Asset (Liability) Fair Value	(31)	(20)
Customer derivatives - Interest rate swaps \| Other Assets
Derivative Financial Instruments
Notional Amount	3,330	3,330
Asset (Liability) Fair Value	229	141
Customer derivatives - Interest rate swaps \| Other Liabilities
Derivative Financial Instruments
Notional Amount	3,330	3,330
Asset (Liability) Fair Value	$ (260)	$ (161)

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

+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-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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