Note 11 - Accounts Payable and Accrued Expenses - Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Trade payables	$ 48,309	$ 41,364
Salaries and other payroll costs	17,977	14,671
Customer advances	576	2,533
Accrued interest	3,524	8,252
Income tax payable	8,824	11,353
Property tax payable	1,884	3,609
Scheduling and transmission	964	1,547
Royalty accrual	1,639	1,818
Other	7,953	6,808
Total	$ 91,650	$ 91,955