Disclosures about Fair Value of Assets and Liabilities - Reconciliation of Unobservable Inputs (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivative liabilities \| Interest Rate Lock Commitments
Reconciliation of significant unobservable inputs, liabilities:
Changes in fair value	$ 2
Balance, end of period	2
Mortgage servicing rights
Reconciliation of significant unobservable inputs, assets:
Balance, beginning of period	66,079	$ 53,670
Additions
Purchased servicing	327	480
Originated servicing	3,125	837
Subtractions
Paydowns	(1,370)	(286)
Changes in fair value due to changes in valuation inputs or assumptions used in the valuation model	(893)	87
Balance, end of period	67,268	$ 54,788
Derivative assets \| Interest Rate Lock Commitments
Subtractions
Changes in fair value	116
Balance, end of period	116
Municipals \| Available-for-sale Securities
Reconciliation of significant unobservable inputs, assets:
Balance, beginning of period	6,688
Subtractions
Paydowns	(258)
Balance, end of period	$ 6,430

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Amount of changes in fair value due to changes in valuation inputs or assumptions used in the valuation model.

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No definition available.

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Amount of originated servicing classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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No definition available.

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Amount of purchased servicing classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

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

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

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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