Commitments and Contingencies - Sublease Income (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Loss Contingencies [Line Items]
2017	$ 343
2018	127
Total	470
New York
Loss Contingencies [Line Items]
2017	165
2018	127
Total	292
Menlo Park
Loss Contingencies [Line Items]
2017	178
2018	0
Total	$ 178

Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Due in Two Years

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- Definition

Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Next Twelve Months

+ References

No definition available.

+ Details

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- Definition

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+ References

No definition available.

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- Definition

Contractually required future rental payments receivable on noncancelable subleasing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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