Revolving Credit Facility and Long-Term Debt - Principal Balances under Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Feb. 23, 2017	Dec. 31, 2016
Line of Credit Facility [Line Items]
Total debt	$ 241,912		$ 324,373
2017 Debt facility	6,969	$ 7,000	0
Less debt issuance costs	(557)		(627)
Less current portion	16,969		10,000
Long-term portion	224,943		314,373
Term Loan
Line of Credit Facility [Line Items]
Total debt	90,000		145,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Total debt	$ 145,500		$ 180,000