Loan Servicing Rights - Components of Loan Servicing Rights and Valuation Allowance (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Servicing asset:
Balance at beginning of period	$ 25,399	$ 24,512
Additions	1,731	659
Amortization	(1,555)	(900)
Balance before valuation allowance at end of period	25,575	24,271
Valuation allowance:
Balance at beginning of period	(31)	(15)
(Additions)/recoveries	(1,412)	(2)
Balance at end of period	(1,443)	(17)
Loan servicing rights, net	$ 24,132	$ 24,254	$ 25,368

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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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

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

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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.

+ References

No definition available.

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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

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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.

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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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No definition available.

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