Fair Value Measurements - Reconciliation of Items Using Level Three Inputs (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($)
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance as of January 1, 2019	$ 977
Fair value adjustments	(67)
Balance as of September 30, 2019	910
Corporate Bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance as of January 1, 2019	3,671
Transfer from level 2 to level 3	1,035
Fair value adjustments	(16)
Balance as of September 30, 2019	$ 4,690

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

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- Definition

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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