Retirement plans (Tables) (Pension Plans, Defined Benefit [Member])

9 Months Ended

Sep. 28, 2014

Pension Plans, Defined Benefit [Member]

Defined Benefit Plan Disclosure [Line Items]

Benefit costs

Our retirement plan costs include costs for qualified and nonqualified plans and are presented in the following table:

In thousands	Thirteen Weeks Ended						Thirty-nine Weeks Ended
	Sept. 28, 2014			Sept. 29, 2013			Sept. 28, 2014			Sept. 29, 2013
Service cost-benefits earned during the period	$	1,358		$	1,942		$	4,066		$	5,823
Interest cost on benefit obligation	42,391			35,149			127,129			105,403
Expected return on plan assets	(58,902		)	(49,447		)	(176,650		)	(148,289		)
Amortization of prior service cost	1,892			1,888			5,675			5,664
Amortization of actuarial loss	11,455			15,779			34,356			47,329
Expense (credit) for company-sponsored retirement plans	$	(1,806	)	$	5,311		$	(5,424	)	$	15,930