Note 9 - Product Warranty Obligations - Recognition of Deferred Revenue Related to Extended Warranties 2 (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Revenue performance obligation	$ 106,575
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue performance obligation	5,140
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue performance obligation	20,809
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue performance obligation	21,053
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue performance obligation	17,432
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue performance obligation	13,661
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue performance obligation	$ 28,480