Note 3 - Long-term Debt - Long-term Debt Summary (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Total outstanding principal	$ 1,857,026	$ 1,860,234
Carrying value of long-term debt	1,836,229	1,837,428
Less current portion	(37,000)	(6,417)
Long-term debt, less current portion and deferred financing costs	1,799,229	1,831,011
Borrowing availability under the Revolving Credit Facility	100,000	100,000
The 2017 Senior Credit Facility [Member]
Senior Credit Facility	632,026	635,234
2024 Notes [Member]
Senior Notes	525,000	525,000
Unamortized deferred loan costs	(6,244)	(6,743)
2026 Notes [Member]
Senior Notes	700,000	700,000
Unamortized deferred loan costs	(8,915)	(9,473)
Unamortized premium	4,881	5,187
2014 Senior Credit Facility [Member]
Unamortized deferred loan costs	$ (10,519)	$ (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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