Commitments and Contingencies - Estimated Lease Future Amortization Expenses (Details) - Lease $ in Thousands	Dec. 31, 2018 USD ($)
2019	$ 986
2020	1,977
2021	2,452
2022	2,954
2023	3,326
Thereafter	16,626
Total future amortization	$ 28,321

Finite-Lived Intangible Assets, Amortization Expense (Benefits), Next Twelve Months

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Finite-Lived Intangible Assets, Amortization Expense (Benefits), Year Five

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Finite-Lived Intangible Assets, Amortization Expense (Benefits), Year Four

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Finite-Lived Intangible Assets, Amortization Expense (Benefits), Year Three

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Finite-Lived Intangible Assets, Amortization Expense (Benefits), Year Two

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Finite-Lived Intangible Assets, Amortization Expense (Benefits), after Year Five

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Total future amortization

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