Note 7 - Employee Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2020

Notes Tables

Schedule of Net Benefit Costs [Table Text Block]

	Three Months Ended June 30,
	2020			2019
Service cost	$	1,334		$	1,100
Interest cost		1,404			1,620
Expected return on plan assets		(1,872	)		(1,496	)
Amortization of prior service cost		29			15
Amortization of net loss		1,163			1,097
Net periodic pension cost	$	2,058		$	2,336

	Six Months Ended June 30,
	2020			2019
Service cost	$	2,668		$	2,200
Interest cost		2,808			3,240
Expected return on plan assets		(3,744	)		(2,992	)
Amortization of prior service cost		58			30
Amortization of net (gain) loss		2,326			2,194
Net periodic pension cost	$	4,116		$	4,672