Note 9 - Employee Retirement Plans - Pension Plan Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair value of plan assets	$ 30,255	$ 30,843	$ 45,378	$ 56,779
Pension Plan [Member]
Fair value of plan assets	30,254	30,843
Pension Plan [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	17,119	14,508
Pension Plan [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets	10,504	10,831
Pension Plan [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets	2,631	5,504
Pension Plan [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member]
Fair value of plan assets	14,927	14,269
Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	14,927	14,212
Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets	0	57
Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Equity Securities [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Debt Security [Member]
Fair value of plan assets	11,962	10,058
Pension Plan [Member] | Defined Benefit Plan, Debt Security [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	2,192	296
Pension Plan [Member] | Defined Benefit Plan, Debt Security [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets	9,770	9,762
Pension Plan [Member] | Defined Benefit Plan, Debt Security [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Debt Security [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Alternative Securities [Member]
Fair value of plan assets	2,631	5,504
Pension Plan [Member] | Defined Benefit Plan, Alternative Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Alternative Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Alternative Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets	2,631	5,504
Pension Plan [Member] | Defined Benefit Plan, Alternative Securities [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Cash and Cash Equivalents [Member]
Fair value of plan assets	734	1,012
Pension Plan [Member] | Defined Benefit Plan, Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value of plan assets	734	1,012
Pension Plan [Member] | Defined Benefit Plan, Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]
Fair value of plan assets	0	0
Pension Plan [Member] | Defined Benefit Plan, Cash and Cash Equivalents [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Fair value of plan assets	$ 0	$ 0