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Note 3 - Long-term Debt (Details Textual) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Interest Paid, Excluding Capitalized Interest, Operating Activities	$ 95,000	$ 105,000
Interest Costs Capitalized	$ 0	$ 0
2024 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage			5.125%
2026 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	5.875%
2027 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	7.00%
The 2019 Senior Credit Facility [Member] \| The 2019 Term Loan [Member]
Debt Instrument, Interest Rate, Effective Percentage	2.70%
The 2017 Senior Credit Facility [Member] \| The 2017 Term Loan [Member]
Debt Instrument, Interest Rate, Effective Percentage	2.40%