Equity (Treasury Stock) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 25, 2011
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Number of shares of common stock repurchased (in shares)	889,791	5,818,731
Total cost of repurchase of treasury shares	$ 30,813	$ 213,624
Open market repurchases
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Number of shares of common stock repurchased (in shares)	806,454	1,102,392
Total cost of repurchase of treasury shares	27,800	42,095
2000 Incentive Plan and 2007 Incentive Plan
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Number of shares of common stock repurchased (in shares)	83,337	78,607
Total cost of repurchase of treasury shares	$ 3,013	$ 2,903
Accelerated stock repurchase programs
Treasury Shares and Accelerated Stock Repurchase Program (ASR)
Number of shares of common stock repurchased (in shares)		4,637,732