Income Taxes - Deferred Tax Effects of Temporary Differences Giving Rise to the Company's Net Deferred Tax Assets (Details) - USD ($) $ in Thousands	Jan. 30, 2016	Jan. 31, 2015	Sep. 30, 2014
Deferred tax assets:
Net operating loss carryforwards	$ 11,296	$ 3,457	$ 3,141
Deferred rent	10,004	10,492	10,138
Employee benefit accruals	3,836	3,596	4,610
Inventory reserves	3,320	5,368	1,262
Grow NJ award benefit, net	2,493
Stock-based compensation	1,212	736	1,134
Federal tax credit carryforwards	618	140
Depreciation and amortization		1,722	107
Other accruals	1,896	2,642	2,458
Other	2,062	2,298	2,026
Deferred tax assets (excluding state net operating loss carryforwards)	36,737	30,451	24,876
Valuation allowance	(2,666)	(1,925)	(1,925)
Deferred tax asset, net of valuation allowance	34,071	28,526	22,951
Deferred tax liability:
Depreciation and amortization	(4,570)
Prepaid expenses	(503)	(541)	(801)
Deferred tax liabilities, gross	(5,073)	(541)	(801)
Net deferred tax assets	$ 28,998	$ 27,985	$ 22,150