Note 7 - Employee Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2017

Notes Tables

Schedule of Net Benefit Costs [Table Text Block]

	Three Months Ended June 30,
	2017			2016
Service cost	$	1,196		$	1,077
Interest cost		1,339			1,307
Expected return on plan assets		(1,462	)		(1,325	)
Amortization of prior service cost		(84	)		(84	)
Amortization of net loss		1,033			1,093
Net periodic pension cost	$	2,022		$	2,068

	Six Months Ended June 30,
	2017			2016
Service cost	$	2,392		$	2,154
Interest cost		2,678			2,614
Expected return on plan assets		(2,924	)		(2,650	)
Amortization of prior service cost		(168	)		(168	)
Amortization of net (gain) loss		2,066			2,186
Net periodic pension cost	$	4,044		$	4,136