Debt - Debt Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Principal Balance
Total debt	$ 36,132	$ 85,797
Less amounts due within one year	(12,868)	(3,631)
Total long-term debt	23,264	82,166
Unamortized Debt Financing Costs
Total debt	72	117
Less amounts due within one year	(23)	(39)
Total long-term debt	49	78
Balance, Net of Financing Costs
Total debt	36,060	85,680
Less amounts due within one year	(12,845)	(3,592)
Total long-term debt	23,215	82,088
bp Loan
Principal Balance
Total debt		50,000
Balance, Net of Financing Costs
Total debt		50,000
NG Advantage debt
Principal Balance
Total debt	25,832	29,535
Unamortized Debt Financing Costs
Total debt	72	117
Balance, Net of Financing Costs
Total debt	25,760	29,418
Term Loan Facility
Principal Balance
Total debt	9,500	5,100
Balance, Net of Financing Costs
Total debt	9,500	5,100
Other debt
Principal Balance
Total debt	800	1,162
Balance, Net of Financing Costs
Total debt	$ 800	$ 1,162