Quarterly report pursuant to Section 13 or 15(d)

Note 13 - Employee Stock Plans (Details Textual)

v3.23.2
Note 13 - Employee Stock Plans (Details Textual) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2023
Jun. 30, 2022
Jun. 30, 2023
Jun. 30, 2022
May 31, 2010
Share-Based Payment Arrangement, Expense $ 3,279 $ 3,153 $ 4,236 $ 5,053  
Restricted Stock Units (RSUs) [Member]          
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)     $ 39.50    
The 2010 Stock Incentive Plan [Member]          
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)         2,130,000
The 2010 Stock Incentive Plan [Member] | Equity Awards [Member]          
Share-Based Payment Arrangement, Expense 2,229 2,801 $ 3,249 3,724  
The 2010 Stock Incentive Plan [Member] | Performance Shares [Member]          
Share-Based Payment Arrangement, Expense 1,961 2,052 $ 1,544 2,711  
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)     $ 37.36    
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount 3,194   $ 3,194    
The 2010 Stock Incentive Plan [Member] | Restricted Stock Units (RSUs) [Member]          
Share-Based Payment Arrangement, Expense 1,318 $ 1,101 2,692 $ 2,342  
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount $ 2,594   $ 2,594