Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 28, 2014		Jun. 29, 2013		Jun. 28, 2014	Jun. 29, 2013
Unrealized gain (loss) on interest rate swaps:
Before income taxes	$ (1,040)		$ 379		$ (1,980)	$ 399
Income taxes	(395)		144		(753)	152
Net of taxes	(645)		235		(1,227)	247
Reclassification of loss into earnings from interest rate swaps (1):
Before income taxes	86	[1]	80	[1]	172	115
Income taxes	32		30		65	44
Net of taxes	54		50		107	71
Amortization of unrealized loss on dedesignated interest rate swaps (1):
Before income taxes	0	[1]	48	[1]	0	158
Income taxes	0		18		0	60
Net of taxes	0		30		0	98
Reclassification of net actuarial gain into earnings from postretirement benefit plans (2):
Before income taxes	(10)	[2]	(10)	[2]	(20)	(19)
Income taxes	(4)		(4)		(7)	(8)
Net of taxes	(6)		(6)		(13)	(11)
Reclassification of prior service credits into earnings from postretirement benefit plans (2):
Before income taxes	(22)	[2]	(22)	[2]	(44)	(44)
Income taxes	(8)		(8)		(17)	(17)
Net of taxes	(14)		(14)		(27)	(27)
Other comprehensive income (loss)	$ (611)		$ 295		$ (1,160)	$ 378

[1] Amounts for cash flow hedges reclassified from accumulated other comprehensive income (loss) to net income were included in interest expense in the Company's Consolidated Condensed Statement of Operations.

[2] Amounts for postretirement plans reclassified from accumulated other comprehensive income (loss) to net income were included in selling and administrative expenses in the Company's Consolidated Condensed Statement of Operations.