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Note 7 - Employee Benefit Plans (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			6 Months Ended
	Jun. 16, 2026	Aug. 01, 2021	Jun. 30, 2026	Jun. 30, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)			0	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)			12,557
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 34,100
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years 4 months 24 days
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 0
The 2021 Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	200,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)			1,600,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Month)		24 months
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)			0.7
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)			117,181	90,076
Share-Based Compensation Arrangement by Share-Based Payment Award, Per Share Weighted Average Price of Shares Purchased (in dollars per share)			$ 18.46	$ 23.68
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 2,100
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 1 month 6 days
The 2011 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	800,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)			16,700,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)			4,300,000