Net Income per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 30, 2013		Mar. 31, 2012
Earnings Per Share, Diluted [Line Items]
Net income attributable to shareholders	$ 77,875		$ 113,628
Weighted average shares outstanding - basic	105,889		112,002
Net effect of various dilutive stock-based compensation awards	1,935		2,075
Weighted average shares outstanding - diluted	107,824		114,077
Net income per share:
Basic	$ 0.74		$ 1.01
Diluted	$ 0.72	[1]	$ 1.00	[1]
Stock Compensation Plan [Member]
Net income per share:
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,360		589

[1] Stock-based compensation awards for the issuance of 1,360 and 589 shares for the first quarters of 2013 and 2012, respectively, were excluded from the computation of net income per share on a diluted basis as their effect was anti-dilutive.