Supplemental Balance Sheet Information - Accrued expenses and other payables (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Accrued expenses and other payables
Compensation related	$ 18,201	$ 17,051
External research and development activities related	41,601	18,721
Sales rebates and returns related	687	3,997
Professional fees and other	14,548	9,829
Total accrued expenses and other payables	$ 75,037	$ 49,598

Accrued liabilities, other accounts payable, and other liabilities, current.

No definition available.

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- Definition

Carrying value as of the balance sheet date of the obligations incurred through that date related to external research and development activities related

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received and amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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No definition available.

+ Details

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- Definition

Accrued Sales Rebates and Returns, Current

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No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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