Investments (Tables)

12 Months Ended

Dec. 30, 2011

Investments [Abstract]

Available-For-Sale Marketable Securities

	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
December 30, 2011
U.S. government debt obligations	$	195.2	$	0.5	$	—		$	195.7
Corporate debt obligations guaranteed by FDIC		66.6		0.2		—			66.8
Corporate debt obligations		201.4		0.8		(0.7	)		201.5
Mortgaged backed debt obligations guaranteed by GNMA		90.9		0.4		(0.1	)		91.2
Certificates of deposit guaranteed by FDIC		1.5		—		—			1.5
Foreign government debt obligations		221.5		1.5		—			223.0
Foreign corporate debt obligations guaranteed by foreign governments		64.1		0.2		(0.1	)		64.2
Total	$	841.2	$	3.6	$	(0.9	)	$	843.9
December 31, 2010
U.S. government debt obligations	$	259.0	$	0.1	$	(0.7	)	$	258.4
Corporate debt obligations guaranteed by FDIC		102.3		0.3		—			102.6
Corporate debt obligations		95.6		0.5		(0.2	)		95.9
Mortgaged backed debt obligations guaranteed by GNMA		175.5		0.8		(1.2	)		175.1
Certificates of deposit guaranteed by FDIC		3.3		—		—			3.3
Foreign government debt obligations		201.4		1.6		(0.9	)		202.1
Foreign corporate debt obligations guaranteed by foreign governments		87.8		0.6		(0.1	)		88.3
Total	$	924.9	$	3.9	$	(3.1	)	$	925.7

Maturities Of Available-For-Sale Marketable Securities

	Amortized Cost		Fair Value
Less than 12 months	$	296.0	$	296.4
Due in 1 to 5 years		454.4		456.3
Due after 5 years		90.8		91.2
Total	$	841.2	$	843.9

Investments In Marketable Securities With Unrealized Losses

	Unrealized Loss					Unrealized Loss
	Less than 12 months					Greater than 12 months						Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
December 30, 2011
Corporate debt obligations	$	81.0	$	(0.7	)	$	—	$	—	$	81.0	$	(0.7	)
Mortgaged backed debt obligations guaranteed by GNMA		31.4		(0.1	)		—		—		31.4		(0.1	)
Foreign government debt obligations guaranteed by foreign governments		24.1		(0.1	)		—		—		24.1		(0.1	)
Total	$	136.5	$	(0.9	)	$	—	$	—	$	136.5	$	(0.9	)
December 31, 2010
U.S. government debt obligations	$	218.6	$	(0.7	)	$	—	$	—	$	218.6	$	(0.7	)
Corporate debt obligations		47.5		(0.2	)		—		—		47.5		(0.2	)
Mortgaged backed debt obligations guaranteed by GNMA		115.7		(1.2	)		—		—		115.7		(1.2	)
Foreign government debt obligations		92.9		(0.9	)		—		—		92.9		(0.9	)
Foreign government debt obligations guaranteed by foreign governments		32.6		(0.1	)		—		—		32.6		(0.1	)
Total	$	507.3	$	(3.1	)	$	—	$	—	$	507.3	$	(3.1	)

Gross Realized Gains And Losses Related To Fixed Income Investments

	2011			2010			2009
Gross realized gains	$	3.8		$	14.9		$	6.0
Gross realized losses1		(4.9	)		(2.7	)		(1.3	)
Total	$	(1.1	)	$	12.2		$	4.7

¹ Includes other-than-temporary impairments of $1.2 million for the year ended December 30, 2011.