Long-term Debt - Summary of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total long-term debt	$ 97,552	$ 85,300
Less current maturities	(1,339)	0
Total long-term debt	96,213	85,300
Revolving Credit Facility
Debt Instrument [Line Items]
Total long-term debt	87,300	$ 85,300
Obligations Under Finance Lease
Debt Instrument [Line Items]
Total long-term debt	$ 10,252