CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 23, 2012	Dec. 25, 2011
Accounts receivable, allowances	$ 17,646	$ 17,275
Property, plant and equipment, accumulated depreciation and amortization	929,432	862,665
Goodwill, accumulated impairment losses	$ 805,218	$ 805,218
Common stock, par value	$ 0.10	$ 0.10
Class A Common Stock
Authorized shares	300,000,000	300,000,000
Issued shares	150,228,385	150,007,446
Treasury shares	2,677,379	2,979,786
Class B Common Stock
Authorized shares	818,385	818,885
Issued shares	818,385	818,885
Treasury shares	0	0