Note 15 - Revenue (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Contract liabilities	$ 64	$ 61
Contract liabilities, current	46	43
Revenue recognized, contract liabilities	43	34
Contract with customer, cash payments received for liabilities that have been deferred	41	47
Other Current Assets [Member]
Disaggregation Of Revenue [Line Items]
Contract assets	2	4
Other Current Liabilities [Member]
Disaggregation Of Revenue [Line Items]
Contract liabilities, current	47	43
Other Long-Term Liabilities [Member]
Disaggregation Of Revenue [Line Items]
Contract liabilities, non-current	$ 17	$ 18