Mortgage Servicing Rights - Schedule of Servicing Income and Expense Included in Mortgage Banking Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Servicing income:
Servicing income	$ 4,793	$ 2,748
Change in fair value of mortgage servicing rights	3,543	(501)
Change in fair value of mortgage servicing rights hedging instruments	(5,256)
Gross servicing income	3,080	2,247
Gross direct servicing expenses	1,795	1,020
Net servicing income	$ 1,285	$ 1,227

Change in fair value of mortgage servicing rights.

No definition available.

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- Definition

Change in fair value of mortgage servicing rights hedging instruments.

+ References

No definition available.

+ Details

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- Definition

Gross direct servicing expenses.

+ References

No definition available.

+ Details

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- Definition

Servicing income.

+ References

No definition available.

+ Details

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- Definition

Servicing income (loss).

+ References

No definition available.

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122596-111746

+ Details

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- Definition

Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability.

+ References

+ Details

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