Commitments, Off-Balance Sheet Arrangements, Legal Proceedings and Regulatory Matters Residential Mortgage Repurchase Reserve (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Residential mortgage repurchase reserve
Balance at beginning of period	$ 24,000
Balance at end of period	25,000	$ 24,000
Mortgage Repurchase Reserve
Residential mortgage repurchase reserve
Balance at beginning of period	987	900
Repurchase provision expense	254	246
Charge offs, net	(125)	(159)
Amount recorded at acquisition	88	0
Balance at end of period	$ 1,204	$ 987

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

+ References

+ Details

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- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

+ References

+ Details

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from business combination.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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