Note 7 - Revenue 2 (Details Textual) - USD ($) $ in Millions	Mar. 31, 2022	Mar. 31, 2021
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Fixed-Price Contract [Member]
Revenue, Remaining Performance Obligation, Amount	$ 624
Revenue, Remaining Performance Obligation, Percentage		79.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	2 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 | Contracts with Price Reopeners [Member]
Revenue, Remaining Performance Obligation, Amount	$ 166
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	1 year