INVESTMENTS (Tables)

9 Months Ended

Sep. 30, 2019

Investments, Debt and Equity Securities [Abstract]

Schedule of Investments in Debt Securities

Investments in debt securities at the end of each period were as follows (in millions):



	September 30, 2019									December 31, 2018
Held-to-maturity	Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Bank time deposits	$	—	$	—	$	—		$	—	$	20.0	$	—	$	—			$	20.0

Available-for-sale
Commercial paper	$	10.9	$	—	$	—		$	10.9	$	56.7	$	—	$	—			$	56.7
U.S. government and agency securities	75.4		0.6		—			76.0		79.7		0.2		(0.7		)		79.2
Foreign government bonds	1.6		—		—			1.6		1.7		—		—				1.7
Asset-backed securities	80.7		0.6		—			81.3		110.6		0.1		(0.5		)		110.2
Corporate debt securities	354.9		2.0		(0.1		)	356.8		459.8		0.1		(4.3		)		455.6
Municipal securities	2.7		—		—			2.7		2.8		—		—				2.8
Total	$	526.2	$	3.2	$	(0.1	)	$	529.3	$	711.3	$	0.4	$	(5.5	)		$	706.2

Schedule of Cost and Fair Value of Investments in Debt Securities, By Contractual Maturity

The cost and fair value of investments in debt securities, by contractual maturity, as of September 30, 2019 were as follows:



	Available-for-Sale
	Cost		Fair Value
	(in millions)
Due in 1 year or less	$	169.9	$	170.3
Due after 1 year through 5 years	292.4		294.5
Instruments not due at a single maturity date	63.9		64.5
	$	526.2	$	529.3

Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value

The following tables present gross unrealized losses and fair values for those investments that were in an unrealized loss position as of September 30, 2019 and December 31, 2018, aggregated by investment category and the length of time that individual securities have been in a continuous loss position (in millions):



	September 30, 2019
	Less than 12 Months				12 Months or Greater					Total
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
Corporate debt securities	$	—	$	—	$	41.4	$	(0.1	)	$	41.4	$	(0.1	)



	December 31, 2018
	Less than 12 Months					12 Months or Greater					Total
	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
U.S. government and agency securities	$	0.7	$	(0.1	)	$	56.5	$	(0.6	)	$	57.2	$	(0.7	)
Asset-backed securities	4.0		—			61.3		(0.5		)	65.3		(0.5		)
Corporate debt securities	177.4		(1.1		)	203.7		(3.2		)	381.1		(4.3		)
	$	182.1	$	(1.2	)	$	321.5	$	(4.3	)	$	503.6	$	(5.5	)

Schedule of Investments in Unconsolidated Affiliates

Investments in these unconsolidated affiliates are recorded in "Long-term Investments" on the consolidated condensed balance sheets, and are as follows:



	September 30, 2019			December 31, 2018
	(in millions)
Equity method investments
Cost	$	10.7		$	9.1
Equity in losses	(3.8		)	(4.7		)
Carrying value of equity method investments	6.9			4.4
Equity securities
Carrying value of non-marketable equity securities	20.1			18.1
Total investments in unconsolidated affiliates	$	27.0		$	22.5