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Amount of interest capitalized during the period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Note 4 - Long-term Debt (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Feb. 18, 2021	Oct. 19, 2020	Jan. 02, 2019
Interest Paid, Excluding Capitalized Interest, Operating Activities	$ 179,000	$ 212,000	$ 95,000
Interest Costs Capitalized	$ 0	$ 0	$ 0
2026 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	5.875%
2027 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	7.00%
2030 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	4.75%				4.75%
Debt Instrument, Face Amount					$ 800,000
2024 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	5.125%
The 2019 Senior Credit Facility [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity						$ 200,000
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%
The Amended 2019 Senior Credit Facility [Member] \| Revolving Credit Facility [Member] \| Subsequent Event [Member]
Line of Credit Facility, Maximum Borrowing Capacity				$ 300,000