Note 6 - Long-term Debt - Future Minimum Principal Payments of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
2022, long-term debt	$ 26,061
2023, long-term debt	82,973
2024, long-term debt	38,461
2025, long-term debt	292,426
2026, long-term debt	37,248
Thereafter, long-term debt	81,353
Total, long-term debt	$ 558,522	$ 496,492

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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