Loan Servicing - Summary of Activity Relating to Mortgage Servicing Rights (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Mortgage servicing rights:
Balance at beginning of year	$ 8,910	$ 2,601
Additions through originations	451	206
Amortization	(339)	(120)
Balance at end of period	9,022	2,687
Valuation allowance:
Balance at beginning of year	424	34
Provision (credit)	(280)
Balance at end of period	144	34
Amortized cost, net	8,878	2,653
Fair value	$ 8,907	$ 2,898

Mortgage servicing rights.

No definition available.

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- Definition

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7524895&loc=d3e120260-111741

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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- Definition

Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
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- Definition

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

+ References

No definition available.

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Amount of increase (decrease) in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from expenses (recoveries) recognized.

+ References

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- Definition

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

+ References

No definition available.

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