v3.8.0.1

Fair Value Measurements - Narrative (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) | Sep. 30, 2017 ft²
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Restructuring charges, sublease | $ | $ 0.5 |
Massachusetts |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Area of real estate property |  | 108,743
Massachusetts | Property Subject to Operating Lease |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Area of real estate property |  | 25,812

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