Number of countries.

No definition available.

Name:	bamm_NumberOfCountries
Namespace Prefix:	bamm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Schedule Of Results Related To Equity Accounted Investees [Line Items]

+ References

No definition available.

+ Details

Name:	bamm_ScheduleOfResultsRelatedToEquityAccountedInvesteesLineItems
Namespace Prefix:	bamm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_EquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=bamm_IfMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=bamm_EquityInterestOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=bamm_AncoFarEastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=bamm_EquityInterestTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=bamm_PrincipalsofIFMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Equity Method Investments - Additional Information (Detail) $ in Thousands	6 Months Ended
	Aug. 01, 2015 USD ($) Country	Jan. 31, 2015 USD ($)	Apr. 30, 2013 USD ($)
Schedule Of Results Related To Equity Accounted Investees [Line Items]
Acquired the equity interest	$ 2,284	$ 2,194
IF [Member]
Schedule Of Results Related To Equity Accounted Investees [Line Items]
Percentage of equity method investment in company	25.00%
Number of countries (over) \| Country	70
Acquired the equity interest			$ 1,800
Equity Interest One [Member] \| IF [Member] \| Anco Far East [Member]
Schedule Of Results Related To Equity Accounted Investees [Line Items]
Percentage of equity method investment in company	45.00%
Equity Interest Two [Member] \| IF [Member] \| Principals of IF [Member]
Schedule Of Results Related To Equity Accounted Investees [Line Items]
Percentage of equity method investment in company	30.00%