Accrued Expenses and Other Current Liabilities - Tabular Disclosure (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Accrued Expenses
Salaries	$ 2,042	$ 4,566
Accrued vacation	4,820	4,672
Accrued incentive compensation	5,868	13,403
Other employee benefits	2,445	1,305
Professional fees	2,360	1,261
Accrued interest	2,761	873
Workforce reduction charges	1,161
Other	8,688	12,157
Total accrued expenses and other current liabilities	$ 30,145	$ 38,237