Note 12 - Employee Retirement Plans - Benefit Obligation and Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension Plan [Member] | UNITED STATES
Benefit obligation at beginning of year	$ 4,075,000	$ 4,203,000
Service cost	105,000	102,000	$ 92,000
Interest cost	98,000	78,000	110,000
Plan amendments	28,000
Actuarial gain	(925,000)	(107,000)
Other	3,000
Benefits paid	(202,000)	(201,000)
Benefit obligation at end of year	3,182,000	4,075,000	4,203,000
Balance	3,598,000	3,575,000
Actual (loss) gain on plan assets	(728,000)	208,000
Defined Benefit Plan, Plan Assets, Contributions by Employer	15,000	16,000
Benefits paid	(202,000)	(201,000)
Balance	2,683,000	3,598,000	3,575,000
Fair value of plan assets	2,683,000	3,598,000	3,575,000
Benefit obligations	3,182,000	4,075,000	4,203,000
Funded status of plans	(499,000)	(477,000)
Current liability	(18,000)	(15,000)
Noncurrent liability	(481,000)	(462,000)
Recognized liability	(499,000)	(477,000)
Net actuarial loss (gain)	259,000	272,000
Prior service cost (credit)	44,000	22,000
Amounts recognized at end of year	303,000	294,000
Pension Plan [Member] | Foreign Plan [Member]
Benefit obligation at beginning of year	736,000	778,000
Service cost	22,000	25,000	26,000
Interest cost	11,000	10,000	12,000
Actuarial gain	(137,000)	(17,000)
Other	(1,000)	(2,000)
Benefits paid	(21,000)	(26,000)
Foreign currency translation	(61,000)	(32,000)
Benefit obligation at end of year	549,000	736,000	778,000
Balance	584,000	598,000
Actual (loss) gain on plan assets	(139,000)	(2,000)
Defined Benefit Plan, Plan Assets, Contributions by Employer	8,000	31,000
Benefits paid	(21,000)	(26,000)
Foreign currency translation	(51,000)	(17,000)
Balance	381,000	584,000	598,000
Fair value of plan assets	381,000	584,000	598,000
Benefit obligations	549,000	736,000	778,000
Funded status of plans	(168,000)	(152,000)
Noncurrent asset	26,000	100,000
Current liability	(7,000)	(7,000)
Noncurrent liability	(187,000)	(245,000)
Recognized liability	(168,000)	(152,000)
Net actuarial loss (gain)	(2,000)	(3,000)
Prior service cost (credit)	(1,000)	1,000
Amounts recognized at end of year	(3,000)	(2,000)
Other Postretirement Benefits Plan [Member]
Benefit obligation at beginning of year	654,000	764,000
Service cost	9,000	10,000	9,000
Interest cost	15,000	15,000	20,000
Plan participants’ contributions	7,000	7,000
Actuarial gain	(209,000)	(105,000)
Benefits paid	(42,000)	(37,000)
Benefit obligation at end of year	434,000	654,000	764,000
Balance	9,000	30,000
Defined Benefit Plan, Plan Assets, Contributions by Employer	31,000	9,000
Plan participants’ contributions	7,000	7,000
Benefits paid	(42,000)	(37,000)
Balance	5,000	9,000	30,000
Fair value of plan assets	5,000	9,000	30,000
Benefit obligations	434,000	654,000	$ 764,000
Funded status of plans	(429,000)	(645,000)
Current liability	(22,000)	(23,000)
Noncurrent liability	(407,000)	(622,000)
Recognized liability	(429,000)	(645,000)
Net actuarial loss (gain)	(226,000)	(22,000)
Prior service cost (credit)	(15,000)	(20,000)
Amounts recognized at end of year	(241,000)	(42,000)
Other Postretirement Benefits Plan [Member] | UNITED STATES
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 0	$ 0