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v3.19.2

Commitments - Additional Information (Details) $ in Millions | 6 Months Ended
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Jun. 30, 2019 USD ($)
Recorded Unconditional Purchase Obligation [Line Items] |
Restricted cash | $ 0.4
Pre-clinical Research Study Obligations [Member] |
Recorded Unconditional Purchase Obligation [Line Items] |
Contractual obligation, due in next twelve months | 1.8
Contractual obligation | $ 2.5
Minimum [Member] |
Recorded Unconditional Purchase Obligation [Line Items] |
Operating and financing lease, lease term | 2 years
Maximum [Member] |
Recorded Unconditional Purchase Obligation [Line Items] |
Operating and financing lease, lease term | 11 years

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