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