Fair Value Measurements - Additional Information (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Redeemable convertible preferred stock call option liability, net	$ 0	$ 0
Transfers between level 1 to level 2	0	0
Transfers between level 2 to level 1	$ 0	$ 0

No definition available.

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

+ Details

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- Definition

Fair value portion of shares that an entity is required to redeem for cash or other assets at a fixed or determinable date or upon the occurrence of an event.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e21216-110875

+ Details

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