Note 8 - Leases - Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Amortization of right-of-use assets	$ 111,559
Interest on lease liabilities	8,346
Operating lease cost	1,080,226	1,049,523
Sublease income	(45,200)
Total lease costs	$ 1,154,931	$ 1,049,523
Weighted-average remaining lease term - financing leases (in years) (Year)	3 years 182 days
Weighted-average remaining lease term - operating leases (in years) (Year)	15 years 73 days
Weighted-average discount rate - financing leases	1.96%
Weighted-average discount rate - operating leases	5.60%