Note 3 - Long-term Debt - Long-term Debt Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Total outstanding principal, including current portion	$ 1,858,630	$ 1,860,234
Long-term debt, less deferred financing costs	1,836,828	1,837,428
Less current portion	(6,417)	(6,417)
Long-term debt, less current portion and deferred financing costs	1,830,411	1,831,011
Borrowing availability under Revolving Credit Facility	100,000	100,000
The 2017 Senior Credit Facility [Member]
Senior Credit Facility	633,630	635,234
2024 Notes [Member]
Senior Notes	525,000	525,000
Unamortized deferred loan costs	(6,494)	(6,743)
2026 Notes [Member]
Senior Notes	700,000	700,000
Unamortized deferred loan costs	(9,194)	(9,473)
Unamortized premium	5,034	5,187
2014 Senior Credit Facility [Member]
Unamortized deferred loan costs	$ (11,148)	$ (11,777)

Total Long term debt including current portion and before unamortized premium or discount.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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