Investments in Marketable Debt Securities (Tables)

9 Months Ended

Sep. 30, 2015

Investments, Debt and Equity Securities [Abstract]

Marketable Debt Securities

Marketable debt securities at September 30, 2015 and December 31, 2014 consisted of the following:

At September 30, 2015	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
U.S. tax-exempt securities	$	504.3	$	2.1	$	.1	$	506.3
U.S. corporate securities		77.4		.2		.1		77.5
U.S. government and agency securities		8.3		.1				8.4
Non-U.S. corporate securities		568.1		2.1		1.2		569.0
Non-U.S. government securities		168.2		1.2				169.4
Other debt securities		67.8		.4				68.2
	$	1,394.1	$	6.1	$	1.4	$	1,398.8
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:

	September 30, 2015			December 31, 2014
	Less than Twelve Months		Twelve Months or Greater	Less than Twelve Months		Twelve Months or Greater
Fair value	$	333.6		$	249.6
Unrealized losses		1.4			.4

Contractual Maturities of Debt Securities

Contractual maturities on marketable debt securities at September 30, 2015 were as follows:

Maturities:	Amortized Cost		Fair Value
Within one year	$	394.0	$	394.6
One to five years		1,000.0		1,004.1
Six to ten years		.1		.1
	$	1,394.1	$	1,398.8