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Recently Issued Accounting Standards - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Oct. 28, 2017
Oct. 28, 2017
Accounting Standard Update 2016-09 [Member]    
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]    
Excess tax benefit in provision for income taxes $ 1.9 $ 4.3