Note 6 - Senior Notes, Credit Facility and Capital Leases (Tables)

12 Months Ended

Dec. 31, 2017

Notes Tables

Schedule of Maturities of Long-term Debt [Table Text Block]

Twelve-month period ending December 31,
2018	$	34,822
2019		34,822
2020		34,822
2021		518,107
Total		622,573
Less: interest		(116,073	)
Principal		506,500
Less: unamortized discount		(4,271	)
Long-term debt	$	502,229

Schedule of Line of Credit Facilities [Table Text Block]

Interest rates:
Spread over the London Interbank Offer Rate	2.25	-	3.25%
Spread over alternative base rate	1.25	-	2.25%
Standby fee per annum on undrawn amounts		0.50%
Covenant financial ratios:
Senior leverage ratio (debt secured by liens/EBITDA)	not more than 2.50:1
Leverage ratio (total debt less unencumbered cash/EBITDA)	not more than 4.00:1
Interest coverage ratio (EBITDA/interest expense)	not less than 3.00:1

Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block]

Twelve-month period ending December 31,
2018	$	6,014
2019		3,500
2020		2,156
2021		844
Total		12,514
Less: imputed interest		(713	)
Net capital lease obligation	$	11,801