Note 8 - Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

	December 31,
	2020									2019
	Pension Plans			SERP			Total			Pension Plans			SERP			Total
Changes in benefit obligation:
Benefit obligation at beginning of year	$	18,114		$	10,356		$	28,470		$	18,317		$	8,808		$	27,125
Service cost		-			152			152			-			117			117
Interest cost		541			322			863			721			363			1,084
Actuarial loss		1,773			3,610			5,383			2,664			1,171			3,835
Benefits paid		(1,650	)		(103	)		(1,753	)		(3,588	)		(103	)		(3,691	)
Benefit obligation at end of year		18,778			14,337			33,115			18,114			10,356			28,470
Changes in plan assets:
Fair value of plan assets at beginning of year		19,939			-			19,939			19,980			-			19,980
Actual return on assets		462			-			462			3,547			-			3,547
Employer contributions		-			103			103			-			103			103
Benefits paid		(1,647	)		(103	)		(1,750	)		(3,588	)		(103	)		(3,691	)
Fair value of plan assets at end of year		18,754			-			18,754			19,939			-			19,939
Funded status at end of year	$	(24	)	$	(14,337	)	$	(14,361	)	$	1,825		$	(10,356	)	$	(8,531	)
Amounts recognized in balance sheets:
Other assets	$	314		$	-		$	314		$	1,825		$	-		$	1,825
Other current liabilities		-			(101	)		(101	)		-			(103	)		(103	)
Long-term pension liability		(338	)		(14,236	)		(14,574	)		-			(10,253	)		(10,253	)
Net amount recognized	$	(24	)	$	(14,337	)	$	(14,361	)	$	1,825		$	(10,356	)	$	(8,531	)
Amounts recognized in accumulated other comprehensive income consist of:
Net actuarial loss	$	8,227		$	7,429		$	15,656		$	6,312		$	4,516		$	10,828

Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Table Text Block]

	December 31,
	2020								2019
	Pension Plans			SERP		Total			Pension Plans			SERP		Total
Projected benefit obligation	$	18,778		$	14,337	$	33,115		$	18,114		$	10,356	$	28,470
Fair value of plan assets		(18,754	)		-		(18,754	)		(19,939	)		-		(19,939	)
	$	24		$	14,337	$	14,361		$	(1,825	)	$	10,356	$	8,531

Schedule of Net Benefit Costs [Table Text Block]

	Years Ended December 31,
	2020			2019			2018
Interest cost on projected benefit obligation	$	541		$	721		$	675
Expected return on plan assets		(1,555	)		(1,491	)		(1,717	)
Recognized actuarial loss		539			643			526
Settlement loss		413			1,110			-
Net periodic pension cost after settlements	$	(62	)	$	983		$	(516	)

	Years Ended December 31,
	2020		2019		2018
Service cost - benefits earned during the period	$	152	$	117	$	108
Interest cost on projected benefit obligation		322		363		295
Recognized actuarial loss		695		616		606
Net periodic pension cost after settlements	$	1,169	$	1,096	$	1,009

Defined Benefit Plan, Assumptions [Table Text Block]

	Discount Rate							Long Term Rate of Return						Salary Scale
	Pension Plans							Pension Plans						Pension Plans
		Corporate		Plants		SERP			Corporate		Plants		SERP		Corporate	Plants	SERP
2019		3.12	%	3.02	%	3.12	%		8.00	%	8.00	%	N/A		N/A	N/A	3.00	%
2020		2.36	%	2.21	%	2.36	%		8.00	%	8.00	%	N/A		N/A	N/A	3.00	%

	Discount Rate							Long Term Rate of Return						Salary Scale
	Pension Plans							Pension Plans						Pension Plans
		Corporate		Plants		SERP			Corporate		Plants		SERP		Corporate	Plants	SERP
2018		3.53	%	3.45	%	3.53	%		8.00	%	8.00	%	N/A		N/A	N/A	3.00	%
2019		4.14	%	4.06	%	4.14	%		8.00	%	8.00	%	N/A		N/A	N/A	3.00	%
2020		3.12	%	3.02	%	3.12	%		8.00	%	8.00	%	N/A		N/A	N/A	3.00	%

Schedule of Allocation of Plan Assets [Table Text Block]

	Percentage of Plan Assets						Target
	December 31,						Allocation
Investment description	2020			2019			2021
Equity securities		-	%		68	%		60	%
Fixed income		40	%		31	%		40	%
Money market		60	%		-	%		-	%
Other		-	%		1	%		-	%
Total		100	%		100	%		100	%

Schedule of Expected Benefit Payments [Table Text Block]

	Projected Benefit Payments
Year	Pension Plans		SERP		Total
2021	$	1,686	$	102	$	1,788
2022		1,028		1,175		2,203
2023		1,351		588		1,939
2024		1,317		581		1,898
2025		1,297		572		1,869
2026-2030		4,651		3,776		8,427