v2.4.0.8

Business Combinations - Additional Information (Detail) (FeedMagnet, USD $)	0 Months Ended
	Apr. 15, 2014	Oct. 31, 2014
FeedMagnet
Business Acquisition [Line Items]
Cash paid in business acquisition	$ 9,300,000
Adjustments to preliminary purchase price allocation		$ 0

X

- Definition

Business Combination Purchase Price Allocation Adjustment

+ References

No definition available.

+ Details

Name:	bv_BusinessCombinationPurchasePriceAllocationAdjustment
Namespace Prefix:	bv_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration