Retirement Plan - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Contribution Plan Disclosure [Line Items]
Matching contributions by employer	4.00%
Employer matching contribution, vesting period	1 year
Section 401(k) plan
Defined Contribution Plan Disclosure [Line Items]
Total contributions	$ 0.4	$ 0.6	$ 0.6