Note 3 - Long-term Debt - Long-term Debt Summary (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Senior Credit Facility	$ 1,863,443
Total outstanding principal	1,863,443	$ 1,781,438
Less current portion	(6,417)
Net carrying value	1,832,197	1,756,747
Borrowing availability under the Revolving Credit Facility	100,000	60,000
2014 Senior Credit Facility [Member]
Senior Credit Facility		556,438
Unamortized deferred loan costs		(12,158)
The 2017 Senior Credit Facility [Member]
Senior Credit Facility	638,443
Unamortized deferred loan costs	(13,047)
2024 Notes [Member]
Senior Credit Facility	525,000
Unsecured Debt	525,000	525,000
Unamortized deferred loan costs	(7,243)	(7,742)
2026 Notes [Member]
Senior Credit Facility	700,000
Unsecured Debt	700,000	700,000
Unamortized deferred loan costs	(10,031)	(10,588)
Unamortized premium	$ 5,492	$ 5,797

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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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