Commitments and Contingencies - Purchase Commitments (Details) - Inventories $ in Thousands	Mar. 31, 2019 USD ($)
Long-term Purchase Commitment [Line Items]
2019	$ 7,194
2020	1,320
2021	1,320
2022	1,320
2023	220
Thereafter	0
Total	$ 11,374

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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