Debt - Future Minimum Principal Payment Obligations (Details) $ in Thousands	Mar. 31, 2018 USD ($)
Long-term Debt, Fiscal Year Maturity [Abstract]
2018	$ 1,000
2019	2,000
2020	2,000
2021	2,000
2022	2,000
Thereafter	190,500
Total outstanding principal balance	199,500
Unamortized deferred financing costs	(2,630)
Long-term debt	$ 196,870