Note 8 - Leases - Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Amortization of right-of-use assets	$ 27,226		$ 82,084
Interest on lease liabilities	2,138		6,010
Operating lease cost	270,042	277,037	810,124	674,137
Sublease income	(10,300)		(32,900)
Total lease costs	$ 289,106	$ 277,037	$ 865,318	674,137
Operating cash flows from financing leases
Operating cash flows from operating leases				41,845
Financing cash flows from financing leases
Weighted-average remaining lease term - financing leases (in years) (Year)		3 years 255 days		3 years 255 days
Weighted-average remaining lease term - operating leases (in years) (Year)		15 years 146 days		15 years 146 days
Weighted-average discount rate - financing leases		2.05%		2.05%
Weighted-average discount rate - operating leases		5.50%		5.50%