Investment in Marketable Debt Securities (Tables)

12 Months Ended

Dec. 31, 2014

Investments, Debt and Equity Securities [Abstract]

Marketable Debt Securities

Marketable debt securities consisted of the following 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
2013	AMORTIZED COST		UNREALIZED GAINS		UNREALIZED LOSSES		FAIR VALUE
U.S. tax-exempt securities	$	214.9	$	1.2			$	216.1
U.S. corporate securities		78.2		.1	$	.1		78.2
U.S. government and agency securities		5.5						5.5
Non-U.S. corporate securities		608.5		1.2		.4		609.3
Non-U.S. government securities		217.3		.7		.5		217.5
Other debt securities		140.5		.4				140.9
	$	1,264.9	$	3.6	$	1.0	$	1,267.5

Marketable Debt Securities Continuous Unrealized Losses

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

At December 31,	2014			2013
	LESS THAN TWELVE MONTHS		TWELVE MONTHS OR GREATER	LESS THAN TWELVE MONTHS		TWELVE MONTHS OR GREATER
Fair value	$	249.6		$	388.3	$	28.4
Unrealized losses		.4			.9		.1

Contractual Maturities of Debt Securities

Contractual maturities at December 31, 2014 were as follows:

Maturities:	AMORTIZED COST		FAIR            VALUE
Within one year	$	423.6	$	424.1
One to five years		841.2		847.9
	$	1,264.8	$	1,272.0