Commitments, Off-Balance Sheet Arrangements, Legal Proceedings and Regulatory Matters Residential Mortgage Repurchase Reserve (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Residential mortgage repurchase reserve
Balance at beginning of period	$ 24,000
Balance at end of period	26,000	$ 24,000
Mortgage Repurchase Reserve
Residential mortgage repurchase reserve
Balance at beginning of period	752	987
Repurchase provision expense	48	345
Adjustments to provision expense	0	(450)
Charge offs, net	(70)	(218)
Amount recorded at acquisition	0	88
Balance at end of period	$ 730	$ 752

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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