Commitments and Contingencies - Minimum Rent Payments and Contingent Rent Expense under Lease Agreements Accounted for Operating Leases as Build-To-Suit Lease Transactions (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Commitments And Contingencies Disclosure [Abstract]
Minimum rent payments recognized as interest expense	$ 12.1	$ 9.9	$ 5.3