Note 6 - Long-term Debt - Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Principal	$ 558,522	$ 496,492
Deferred Financing Costs, Net	(13,803)	(13,878)
Balance	544,719	482,614
Principal, Current	(26,061)	(11,255)
Deferred Financing Costs, Net, Current	0	0
Balance, Current	(26,061)	(11,255)
Principal, Non-current	532,461	485,237
Deferred Financing Costs, Net, Non-current	(13,803)	(13,878)
Balance, Non-current	518,658	471,359
Revolving Credit Facility [Member]
Principal	44,500	45,000
Deferred Financing Costs, Net	(190)	(341)
Balance	44,310	44,659
Term Facility [Member]
Principal	284,170	280,993
Deferred Financing Costs, Net	(9,050)	(9,492)
Balance	275,120	271,501
First Senior Secured Credit Agreement [Member]
Principal	107,695	107,695
Deferred Financing Costs, Net	(2,090)	(1,784)
Balance	105,605	105,911
Second Senior Secured Credit Agreement [Member]
Principal	120,281	61,120
Deferred Financing Costs, Net	(2,473)	(2,261)
Balance	117,808	58,859
Notes Payable, Other Payables [Member]
Principal	842	1,684
Deferred Financing Costs, Net	0	0
Balance	842	1,684
Other Debt [Member]
Principal	1,034	0
Deferred Financing Costs, Net	0	0
Balance	$ 1,034	$ 0