Significant Accounting Policies (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 24, 2012	Jun. 26, 2011	Jun. 24, 2012	Jun. 26, 2011
Pension and post retirement plans:
Unamortized gain/loss, Pre-Tax	$ 3,106	$ (31,621)	$ 6,031	$ (30,346)
Unamortized gain/loss, Tax	(1,242)	12,654	(2,412)	12,144
Unamortized gain/loss, After-Tax	1,864	(18,967)	3,619	(18,202)
Prior service cost, Pre-tax	(258)	(258)	(533)	(533)
Prior service cost, Tax	103	103	213	213
Prior service cost, After-Tax	(155)	(155)	(320)	(320)
Other comprehensive loss related to equity investments, Pre-Tax	(1,178)	(296)	(2,154)	747
Other comprehensive loss related to equity investments, Tax	471	118	862	(299)
Other comprehensive loss related to equity investments, After-Tax	(707)	(178)	(1,292)	448
Comprehensive income (loss), Pre-Tax	1,670	(32,175)	3,344	(30,132)
Comprehensive income (loss), Tax	(668)	12,875	(1,337)	12,058
Comprehensive income (loss), After-Tax	$ 1,002	$ (19,300)	$ 2,007	$ (18,074)

Tax effect of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

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