Restructuring (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Restructuring and Related Activities [Abstract]
Restructuring charges recognized	$ 624
Restructuring charges accrued	438us-gaap_RestructuringReserve
Changes in restructuring charges
Original Charges and Amounts Accrued	624us-gaap_RestructuringCharges
Amounts Paid	186us-gaap_PaymentsForRestructuring
Amounts Accrued	438us-gaap_RestructuringReserve
Employee severance, benefits and related costs
Restructuring and Related Activities [Abstract]
Restructuring charges accrued	438
Changes in restructuring charges
Original Charges and Amounts Accrued	624
Amounts Paid	186
Amounts Accrued	438
Research and development expense
Changes in restructuring charges
Original Charges and Amounts Accrued	106
Selling, general and administrative expenses
Changes in restructuring charges
Original Charges and Amounts Accrued	$ 518

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of costs incurred to date for the specified restructuring cost.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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-Subparagraph (b)

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

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