Pension and other postretirement benefits (Tables)

9 Months Ended

Sep. 29, 2013

Net Benefit Cost of Pension and Postretirement Benefit Plans

Net benefit cost of pension and postretirement benefit plans consisted of the following:

	Pension Three Months Ended						Postretirement Benefits Three Months Ended				Pension Nine Months Ended						Postretirement Benefits Nine Months Ended
	September  29, 2013			September  30, 2012			September  29, 2013		September  30, 2012		September  29, 2013			September  30, 2012			September  29, 2013		September  30, 2012
	(Dollars in thousands)
Service cost	$	432		$	696		$	176	$	159	$	1,361		$	2,085		$	501	$	475
Interest cost		4,333			4,115			543		473		12,614			12,366			2,084		1,419
Expected return on Plan assets		(5,784	)		(5,043	)		—		—		(17,328	)		(15,128	)		—		—
Net amortization and deferral		1,556			1,604			137		123		4,380			4,814			1,069		368
Settlement charge		—			—			—		—		—			(124	)		—		—
Curtailment charge		—			—			—		—		—			111			—		—
Net benefit cost	$	537		$	1,372		$	856	$	755	$	1,027		$	4,124		$	3,654	$	2,262