Commitments and Contingencies - Facility Leases (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Schedule of Facility Leases [Line Items]
2018	$ 21,085
2019	23,838
2020	26,257
2021	27,650
2022	6,837
Thereafter	0
Total	$ 105,667

Capital and facility leases, future minimum lease payments due

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- Definition

Capital and facility leases, future minimum lease payments due in five years

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- Definition

Capital and facility leases, future minimum lease payments due in four years

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- Definition

Capital and facility leases, future minimum lease payments due thereafter

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- Definition

Capital and facility leases, future minimum payments due in three years

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- Definition

Capital and facility leases, future minimum payments due in two years

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- Definition

Capital and facility leases, future minimum payments due, next twelve months

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- Definition

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.

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