Commitments and Contingencies - Schedule of Future Royalty Payments (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2019	$ 1,052
2020	1,402
2021	1,402
2022	1,683
2023	1,683
2024 and thereafter	5,609
Total future minimum royalty payments	12,831
Less: amount representing interest	(5,711)
Present value of future minimum royalty payments	$ 7,120

Contractual Obligation, Future Minimum Payments, Interest Included in Payments

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Contractual Obligation, Future Minimum Payments, Present Value of Net Minimum Payments

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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Amount of contractual obligation due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of contractual obligation due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of contractual obligation due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of contractual obligation due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of contractual obligation due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of contractual obligation maturing in the remainder of the fiscal year following the latest fiscal year ended.

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