Note 5 - Supplemental Balance Sheet Information - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Balance, beginning of year		$ 9,695	$ 5,775	$ 6,098
Bad debt expense (1)	[1]	(1,259)	8,188	3,155
Write-offs and adjustments		(1,212)	(4,268)	(3,478)
Balance, end of year		$ 7,224	$ 9,695	$ 5,775

[1] The Company recorded bad debt expense (reversals) of less than ($0.1) million, $5.3 million and $0.4 million in 2019, 2018 and 2017, respectively, as part of the restructuring efforts (see Note 4) and was primarily due to the exiting of certain low-return businesses mainly in foreign locations.