Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended
Jan. 01, 2018	Mar. 31, 2018
Accounting Standards Update No. 2017-01 [Member] \| General and Administrative Expenses [Member]
Summary Of Significant Accounting Policies [Line Items]
Increase in general and administrative expenses		$ 1.6
Accounting Standards Update 2014-09 [Member]
Summary Of Significant Accounting Policies [Line Items]
Adjustment to retained earnings	$ 1.9

Amount of the effect of a change in accounting principle on operating profit or loss.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22499-107794

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22580-107794

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22583-107794

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