Supplemental Stockholders' Equity Information - Reclassifications out of Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 25, 2012
Reclassification out of accumulated other comprehensive income (loss):
Income from continuing operations	$ 2,889		$ 8,686
Income tax expense	2,967		1,401
Funded Status of Benefit Plans [Member] | Reclassification out of accumulated other comprehensive income (loss) [Member]
Reclassification out of accumulated other comprehensive income (loss):
Amortization of prior service credit	(4,179)	[1]
Recognized actuarial loss	11,063	[1]
Income from continuing operations	6,884
Income tax expense	2,794
Total reclassification, net of tax	$ 4,090

[1] These items are included in the components of net periodic benefit cost for pension and other retirement benefits. See Note 9 for additional information.