Commitments and Contingencies - Schedule of Future Royalty Payments (Details) $ in Thousands	Sep. 30, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2018	$ 290
2019	1,451
2020	1,451
2021	1,451
2022	1,741
2023 and thereafter	7,545
Total future minimum royalty payments	13,929
Less: amount representing interest	(6,483)
Present value of future minimum royalty payments	$ 7,446

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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