Note 14 - Stockholders' Equity (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Common Stock, Shares Authorized (in shares)	60,000,000	60,000,000
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.375	$ 0.375
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)	1,193,414
Payments for Repurchase of Common Stock	$ 15,000,000.0	$ (0)	$ (0)
Stock Repurchased During Period, Shares (in shares)	196,982	0
Stock Repurchased During Period, Average Cost Per Share (in dollars per share)	$ 76.13
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 1,193,414