Earnings Per Share (Computation Of Earnings Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Oct. 01, 2011	Jul. 02, 2011	Apr. 02, 2011	Dec. 31, 2010	Oct. 02, 2010	Jul. 03, 2010	Apr. 03, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Earnings (Loss) Per Share [Abstract]
Weighted average common shares outstanding	52,108	53,339	54,546	55,353	56,332	56,739	57,489	58,016	53,854	57,143	59,306
Effect of dilutive securities outstanding									337	285	119
Diluted weighted average shares outstanding	52,354	53,628	54,958	55,774	56,692	56,998	57,737	58,265	54,191	57,428	59,425
Income from continuing operations	$ 32,859	$ 34,187	$ 33,169	$ 30,128	$ 29,635	$ 27,247	$ 22,185	$ 25,547	$ 130,343	$ 104,614	$ 48,491
Income (loss) from discontinued operations	2,185	10,814	(205)	31,506	(1,418)	(1,096)	492	(814)	44,300	(2,836)	(1,387)
Net income	$ 35,044	$ 45,001	$ 32,964	$ 61,634	$ 28,217	$ 26,151	$ 22,677	$ 24,733	$ 174,643	$ 101,778	$ 47,104
Income from continuing operations, Basic per share	$ 0.63	$ 0.64	$ 0.60	$ 0.54	$ 0.53	$ 0.48	$ 0.38	$ 0.44	$ 2.42	$ 1.83	$ 0.81
Income (loss) from discontinued operations, Basic per share	$ 0.04	$ 0.20	$ 0.00	$ 0.57	$ (0.03)	$ (0.02)	$ 0.01	$ (0.01)	$ 0.82	$ (0.05)	$ (0.02)
Net income, Basic per share	$ 0.67	$ 0.84	$ 0.60	$ 1.11	$ 0.50	$ 0.46	$ 0.39	$ 0.43	$ 3.24	$ 1.78	$ 0.79
Income from continuing operations, Diluted per share	$ 0.63	$ 0.64	$ 0.60	$ 0.54	$ 0.53	$ 0.48	$ 0.38	$ 0.44	$ 2.40	$ 1.82	$ 0.81
Income (loss) from discontinued operations, Diluted per share	$ 0.04	$ 0.20	$ 0.00	$ 0.56	$ (0.03)	$ (0.02)	$ 0.01	$ (0.02)	$ 0.82	$ (0.05)	$ (0.02)
Net income, Diluted per share	$ 0.67	$ 0.84	$ 0.60	$ 1.10	$ 0.50	$ 0.46	$ 0.39	$ 0.42	$ 3.22	$ 1.77	$ 0.79