Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities Residential Mortgage Repurchase Reserve (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Residential mortgage repurchase reserve
Balance at beginning of period	$ 24,000
Amount recorded at acquisition	88	$ 0
Balance at end of period	24,000	24,000
Mortgage Repurchase Reserve
Residential mortgage repurchase reserve
Balance at beginning of period	987	900
Repurchase provision expense	345	246
Adjustments to provision expense	(450)	0
Charge offs, net	(218)	(159)
Balance at end of period	$ 752	$ 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

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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

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- Definition

Amount of increase (decrease) in valuation and qualifying accounts and reserves.

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

+ References

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