Property and Equipment - Additional Information (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
|
| Property Plant And Equipment [Abstract] | ||||
| Loss on disposal of property and equipment | $ 0.1 | $ 1.1 | $ 1.2 | $ 1.7 |