Class of warrant or right exercised.

No definition available.

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- Definition

Class of warrant or right expiration date.

+ References

No definition available.

+ Details

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- Definition

Class of warrant or right forfeitures and expirations.

+ References

No definition available.

+ Details

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

+ Details

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i)(2))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Subparagraph 2

-Article 4

+ Details

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Article 4

+ Details

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Warrants - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended		0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Jun. 24, 2013	Dec. 31, 2012
Class of Warrant or Right [Line Items]
Warrants outstanding				6,512,650
Warrants exercised	160,676blue_ClassOfWarrantOrRightExercised	102,394blue_ClassOfWarrantOrRightExercised
Cancellation and expiration of warrants	0
Outstanding warrant liability	$ 0us-gaap_WarrantsAndRightsOutstanding	$ 0us-gaap_WarrantsAndRightsOutstanding
Warrants to Purchase Common Stock [Member]
Class of Warrant or Right [Line Items]
Warrants outstanding			337,952
Lot One [Member]
Class of Warrant or Right [Line Items]
Warrants outstanding			307,648
Exercisable common stock, price per share			12.55
Lot Two [Member]
Class of Warrant or Right [Line Items]
Warrants outstanding			30,304
Exercisable common stock, price per share			6.19
Minimum [Member]
Class of Warrant or Right [Line Items]
Expiration date of common stock exercise			Nov. 16, 2015
Maximum [Member]
Class of Warrant or Right [Line Items]
Expiration date of common stock exercise			Apr. 15, 2019