Stock Incentive Plans - 2014 Management Incentive Plan Restricted Stock Units Award Activity (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Nov. 07, 2016	Oct. 15, 2014	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Aggregate fair value (in millions)
Annual installment amount	100.00%
Management Incentive Plan 2014
Aggregate fair value (in millions)
Annual installment amount		25.00%
Restricted Stock | Chief Financial Officer
Restricted shares *
Restricted common stock granted (in shares)	233,863
Restricted Stock | Management Incentive Plan 2014
Restricted shares *
Beginning balance (in shares)			50,625	52,140
Vested (in shares)			(50,625)	(1,432)	(133,452)
Ending balance (in shares)			0	50,625	52,140
Fair value on grant date
Beginning balance (in dollars per share)			$ 5.90	$ 42.19
Ending balance (in dollars per share)				$ 5.90	$ 42.19
Restricted Stock | Management Incentive Plan 2014 | Chief Financial Officer
Restricted shares *
Restricted common stock granted (in shares)	233,863
Beginning balance (in shares)			233,863	233,863
Vested (in shares)			(126,152)
Forfeitures and cancellations (in shares)			(107,711)
Ending balance (in shares)			0	233,863	233,863
Fair value on grant date
Granted, price on grant date (in dollars per share)	$ 4.24
Beginning balance (in dollars per share)			$ 4.24	$ 4.24
Ending balance (in dollars per share)			$ 0	$ 4.24	$ 4.24
Aggregate fair value (in millions)
Granted, aggregate fair value	$ 1.0
Beginning balance, aggregate fair value			$ 1.0	$ 1.0
Ending balance, aggregate fair value			$ 0.0	$ 1.0	$ 1.0