Note 4 - Revenue From Contracts With Customers - Contract Liabilities (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Total contract liabilities - beginning of period	[1]	$ 6,503	$ 4,873
Other contract additions, net		6,905	210
Revenue recognized		(6,938)	(877)
Contract settlements		0	(3,129)
Total contract liabilities - end of period		$ 6,470	$ 1,077

[1] For the beginning balance in 2021 and 2020, total contract liabilities included $186 thousand and $192 thousand, respectively that were classified as long term.