Note 6 - Long-term Debt - Maturities of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
2022	$ 41,673
2023	827,720
2024	0
2025	300,000
2026	0
Thereafter	1,900,000
Total outstanding principal of long-term debt	$ 3,069,393	$ 3,949,823

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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