Property and Equipment - Additional Information (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Property Plant And Equipment [Line Items] | |||
| Depreciation expense | $ 3.1 | $ 1.8 | $ 1.1 |
| Software and Construction in Progress | |||
| Property Plant And Equipment [Line Items] | |||
| Assets held under capital lease | 1.6 | 1.6 | |
| Assets held under capital lease, accumulated amortization | $ 0.4 | $ 0.1 | |