Note 6 - Notes Payable - Summary of Principal Payment Requirements (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
2019 (Remainder)	$ 1,546
2020	69,919
2021	8,553
2022	8,866
2023	9,191
Thereafter	876,122
Total	$ 974,197	$ 925,613

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 of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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