Restricted Securities Available For Sale (Tables)

3 Months Ended

Mar. 31, 2013

Restricted Securities Available For Sale [Abstract]

Schedule Of Restricted Securities Available For Sale

(In millions)	As of March 31, 2013
	Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
US Government and agency securities	$	21.4	$	–	$	(0.1	)	$	21.3
Commercial paper		19.9		–		–			19.9
Corporate bonds		3.1		–		–			3.1
Certificates of deposit		3.2		–		–			3.2
Total restricted securities available for sale	$	47.6	$	–	$	(0.1	)	$	47.5

(In millions)	As of December 31, 2012
	Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
US Government and agency securities	$	20.6	$	–	$	(0.1	)	$	20.5
Commercial paper		18.9		–		(0.1	)		18.8
Corporate bonds		3.3		–		–			3.3
Certificates of deposit		3.3		–		–			3.3
Foreign Government bonds		0.2		–		–			0.2
Total restricted securities available for sale	$	46.3	$	–	$	(0.2	)	$	46.1

Schedule Of Cost And Estimated Fair Values Of Debt Securities By Contractual Maturity

(In millions)	As of
	March 31, 2013				December 31, 2012
	Cost		Estimated Fair Value		Cost		Estimated Fair Value
Contractual Maturity
Within one year	$	35.0	$	34.9	$	33.8	$	33.7
Over one year to five years		8.9		8.9		8.6		8.6
Over five years to ten years		3.7		3.7		3.9		3.8
Total restricted securities available for sale	$	47.6	$	47.5	$	46.3	$	46.1