Commitments and Contingencies - Schedule of Gross Future Minimum Annual Rental Commitments (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Leases [Abstract]
2019 (remaining 6 months)	$ 1,478
2020	3,038
2021	3,127
2022	3,220
2023	1,694
2024	1,745
Total undiscounted rent payments	14,302
Present value discount	(2,135)
Present value	12,167
Current portion of operating lease liability (included as a component of accrued expenses)	2,229
Noncurrent operating lease liabilities	9,938
Total operating lease liability	$ 12,167

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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