Note 5 - Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2021

Notes Tables

Schedule of Net Benefit Costs [Table Text Block]

	Three Months Ended September 30,						Nine Months Ended September 30,
	2021			2020			2021			2020
Service cost	$	1,455		$	1,334		$	4,365		$	4,002
Interest cost		1,248			1,404			3,744			4,212
Expected return on plan assets		(2,313	)		(1,872	)		(6,939	)		(5,616	)
Amortization of prior service cost		99			29			297			87
Amortization of net loss		1,125			1,163			3,375			3,489
Net periodic pension cost	$	1,614		$	2,058		$	4,842		$	6,174