Ownership percentage held by affiliate in variable interest entity.

No definition available.

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph b

-URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5728-111685

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=52262685&loc=d3e5747-111685

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_VariableInterestEntityLineItems
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Balance Type:	na
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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=52262685&loc=SL6759159-111685

+ Details

Name:	us-gaap_VariableInterestEntityOwnershipPercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=bamm_AndersonPrivateCapitalPartnersILpMember
Namespace Prefix:
Data Type:	na
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Variable Interest Entities - Additional Information (Detail) (Yogurt Mountain Holding LLC [Member], USD $) In Millions, unless otherwise specified	0 Months Ended
	Jan. 31, 2015	Dec. 23, 2014	Dec. 22, 2014	Jul. 19, 2013	Jul. 18, 2013	Jan. 31, 2015
Variable Interest Entity [Line Items]
Ownership percentage in consolidated VIE	50.001%	50.001%	50.00%	50.00%	40.00%
Variable interest entity, investment amount	$ 3.1					$ 3.1
Anderson Private Capital Partners I, L.P [Member]
Variable Interest Entity [Line Items]
Variable interest entity, ownership interest held by APCP		49.999%