Recent Accounting Pronouncements - Additional Information (Detail) - ASU 2016-09 [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Recognition of an excess tax benefit and deficiency	$ 1.5	$ 1.2
Increase in effective tax rate due to recognition of an excess tax benefit and deficiency	15.60%	5.90%

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration