Investments in Marketable Debt Securities (Tables)

3 Months Ended

Mar. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Marketable Debt Securities

Marketable debt securities at March 31, 2015 and December 31, 2014 consisted of the following:

At March 31, 2015	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. tax-exempt securities	$	362.4	$	.8	$	.2	$	363.0
U.S. corporate securities		69.5		.4				69.9
U.S. government and agency securities		9.1		.1				9.2
Non-U.S. corporate securities		516.8		3.9		.1		520.6
Non-U.S. government securities		167.2		2.1				169.3
Other debt securities		94.7		.5				95.2
	$	1,219.7	$	7.8	$	.3	$	1,227.2
At December 31, 2014	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. tax-exempt securities	$	362.9	$	.8	$	.3	$	363.4
U.S. corporate securities		80.9		.6				81.5
U.S. government and agency securities		8.0						8.0
Non-U.S. corporate securities		528.1		3.9				532.0
Non-U.S. government securities		192.1		2.0				194.1
Other debt securities		92.8		.3		.1		93.0
	$	1,264.8	$	7.6	$	.4	$	1,272.0

Marketable Debt Securities Continuous Unrealized Losses

Marketable debt securities with continuous unrealized losses and their related fair values were as follows:

	March 31, 2015			December 31, 2014
	Less than Twelve Months		Twelve Months or Greater	Less than Twelve Months		Twelve Months or Greater
Fair value	$	172.2		$	249.6
Unrealized losses		.3			.4

Contractual Maturities of Debt Securities

Contractual maturities on marketable debt securities at March 31, 2015 were as follows:

Maturities:	Amortized Cost		Fair Value
Within one year	$	337.9	$	338.5
One to five years		881.8		888.7
	$	1,219.7	$	1,227.2