Investments in Marketable Debt Securities (Tables)

6 Months Ended

Jun. 30, 2019

Available For Sale Securities [Abstract]

Marketable Debt Securities

Marketable debt securities at June 30, 2019 and December 31, 2018 consisted of the following:

	AMORTIZED		UNREALIZED		UNREALIZED		FAIR
At June 30, 2019	COST		GAINS		LOSSES		VALUE
U.S. tax-exempt securities	$	329.3	$	2.0	$	.1	$	331.2
U.S. corporate securities		162.5		1.8				164.3
U.S. government and agency securities		106.2		1.0				107.2
Non-U.S. corporate securities		310.7		2.5		.2		313.0
Non-U.S. government securities		69.9		.3				70.2
Other debt securities		130.3		1.2		.1		131.4
	$	1,108.9	$	8.8	$	.4	$	1,117.3

	AMORTIZED		UNREALIZED		UNREALIZED		FAIR
At December 31, 2018	COST		GAINS		LOSSES		VALUE
U.S. tax-exempt securities	$	326.0	$	.3	$	1.2	$	325.1
U.S. corporate securities		147.6		.2		.4		147.4
U.S. government and agency securities		98.9		.2		.4		98.7
Non-U.S. corporate securities		272.5		.4		1.6		271.3
Non-U.S. government securities		55.9		.1		.1		55.9
Other debt securities		122.6		.2		.8		122.0
	$	1,023.5	$	1.4	$	4.5	$	1,020.4

Marketable Debt Securities Continuous Unrealized Losses

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

	June 30, 2019				December 31, 2018
	LESS THAN		TWELVE MONTHS		LESS THAN		TWELVE MONTHS
	TWELVE MONTHS		OR GREATER		TWELVE MONTHS		OR GREATER
Fair value	$	27.1	$	207.3	$	252.8	$	397.9
Unrealized losses				.4		.8		3.7

Contractual Maturities of Debt Securities

Contractual maturities on marketable debt securities at June 30, 2019 were as follows:

	AMORTIZED		FAIR
Maturities:	COST		VALUE
Within one year	$	295.8	$	296.2
One to five years		770.7		778.7
Six to ten years		13.2		13.2
More than ten years		29.2		29.2
	$	1,108.9	$	1,117.3