Commitments and Contingencies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2015 Claim Matter	Feb. 01, 2014 Claim Matter
Commitments And Contingencies Textual [Abstract]
Number of matters required accrual	0bamm_NumberOfMattersRequiredAccruals	0bamm_NumberOfMattersRequiredAccruals
Number of asserted or unasserted claims	0bamm_LossContingencyNumberOfClaims	0bamm_LossContingencyNumberOfClaims
Obligation of liabilities	$ 0us-gaap_ContractualObligation	$ 0us-gaap_ContractualObligation

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

No definition available.

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant