Amendments to the Accounting Standards Codification - Additional Information (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease right of use asset	$ 4,127
Operating lease liability	4,466
ASU 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating lease right of use asset	3,500
Operating lease liability	3,800
Cumulative effect adjustment	$ 45

Amount of the related income tax effect of a cumulative effect on retained earnings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Amount of lessee's right to use underlying asset under operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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