Stockholders' Equity (Details Textual) (USD $)	12 Months Ended			1 Months Ended				12 Months Ended						1 Months Ended	12 Months Ended			12 Months Ended			1 Months Ended		12 Months Ended
	Dec. 31, 2011 M Y	Jan. 01, 2011 Y	Jan. 02, 2010 Y	Mar. 01, 2011 Monte Carlo Model [Member] Y	Mar. 03, 2010 Monte Carlo Model [Member] Y	Mar. 31, 2011 Performance Shares [Member]	Mar. 31, 2010 Performance Shares [Member]	Dec. 31, 2011 Performance Shares [Member]	Dec. 31, 2011 Restricted stock grants [Member]	Jan. 01, 2011 Restricted stock grants [Member]	Dec. 31, 2011 Share Repurchase Program 2010 [ Member]	Jan. 01, 2011 Share Repurchase Program 2010 [ Member]	May 12, 2010 Share Repurchase Program 2010 [ Member]	Sep. 30, 2011 Share Repurchase Program 2011 [Member]	Dec. 31, 2011 Share Repurchase Program 2011 [Member]	Jan. 01, 2011 Share Repurchase Program 2007 [Member]	May 31, 2007 Share Repurchase Program 2007 [Member]	Dec. 31, 2011 Stock Incentive Plan 2005 [Member]	Dec. 31, 2011 Stock Incentive Plan 2003 [Member]	Dec. 31, 2011 2005 Stock Incentive Plans restricted stock [Member]	Mar. 01, 2011 Retirement-Eligible Employees [Member] Performance Shares [Member]	Mar. 03, 2010 Retirement-Eligible Employees [Member] Performance Shares [Member]	Dec. 31, 2011 Retirement-Eligible Employees [Member] Performance Shares [Member]	Dec. 31, 2011 Retirement-Eligible Employees [Member] Restricted stock grants [Member]	Jan. 01, 2011 Retirement-Eligible Employees [Member] Restricted stock grants [Member]	Dec. 31, 2011 Series A Preferred Stock [Member]
Class of Stock [Line Items]
Authorized shares of preferred stock	20,000,000																									112,500
Share-based Compensation Arrangements by Share-based Payment Award (Textual) [Abstract]
Repurchase of common stock													5,000,000				3,000,000
Share Repurchase in the open market	4,345,262	2,505,437									4,060,842	939,158			234,900	1,490,131
Cumulative purchase of common stock																3,000,000
Remaining value of repurchasing stock															$ 188,674
Total cost of shares repurchase in the open market	217,118,000	116,386,000									205,800,000	47,382,000			11,326,000	69,004,000
Total cost of cumulative purchase of common stock																106,916,000
Average cost per share of shares repurchased in the open market											$ 50.68	$ 50.45			$ 48.22	$ 46.31
Cumulative average cost per share of shares purchased in the open market																$ 35.64
Common stock issued	52,184,730	51,712,674	50,617,795
Maximum number of share may be subject to restricted stock awards																				2,725,000
Common stock reserved for stock based compensation awards																		7,150,000	5,000,000
Expected option life	4.1	4.2	3.72	2.83	2.83
Contractual term of share based awards																		10 years	10 years
Percentage of of stock option to vest annually with respect to awards																		33.00%	33.00%
Period after which stock option granted will vest, issued from 2009																		3 years
Shares available for future grants																		1,757,481	80,496	826,331
Percentage of stock option to vest after the initial 6 months																			25.00%
Percentage of stock option to vest annually with respect to awards additionally after six months																			25.00%
Minimum age attainment for Retirement Eligibility	60 years
Minimum years of continuous employment to be Retirement Eligible	at least five years
Total unrecognized cost related to unvested stock based compensation awards granted	23,090,000
Weighted average period for cost to be recognized	22
Tax (benefit) realized from exercise of stock options	12,055,000	1,069,000	0
Company's outstanding common stock														$ 200,000,000
Restricted shares/units, Vested									144,658	1,300											35,050	34,300		37,600	36,750
Grant date fair value of restricted units									$ 47.65	$ 43.28														$ 55.57	$ 43.28
Granted to Retirement-Eligible employees, vesting period for restricted units																							3 years	3 years
Performance Shares, Granted						80,050	75,750	80,050	229,943
Number of shares surrendered by employees in satisfaction of certain payroll tax obligations	49,520	76,148
Stockholders Equity (Textual) [Abstract]
Authorized shares of preferred stock, par value	$ 0.01	$ 0.01
Preferred stock issued	0	0
Preferred stock outstanding	0	0
Stock options granted	364,800
Company's performance to date shares that the company is obligated to issue at the end of performance period	18,613
Shares Re-purchased under the Company's share repurchase programs	4,295,742	2,429,289