Note 8 - Leases - Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Operating lease ROU assets	$ 44,033
Operating lease liabilities	52,510
Operating lease cost	1,892
Short-term lease cost	34
Variable lease cost	246
Total lease cost	2,172
Operating cash flows from operating leases	2,025
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 21
Weighted-average remaining lease term-operating leases (in years) (Year)	8 years
Weighted average discount rate-operating leases	3.80%