Income Taxes - Deferred Income Taxes - Narrative (Detail) - USD ($) $ in Thousands	Jul. 31, 2016	May 01, 2016		Aug. 02, 2015
Income Taxes [Line Items]
Non-current deferred tax asset	$ 1,942	$ 2,319	[1]	$ 4,406
Non-current deferred tax liability	1,532	1,483	[1]	1,072
U.S. Tax Authorities [Member]
Income Taxes [Line Items]
Non-current deferred tax asset	1,400	1,700		3,500
China [Member]
Income Taxes [Line Items]
Non-current deferred tax asset	561	572		914
Canada [Member]
Income Taxes [Line Items]
Non-current deferred tax liability	$ 1,500	$ 1,500		$ 1,100

[1] Derived from audited financial statements.