Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Assets and liabilities measured at fair value on a recurring basis

The following table provides a summary of assets and liabilities measured at fair value on a recurring basis and as reported in the Condensed Consolidated Balance Sheets (in millions):

	Fair Value Measurements at March 31, 2019										Fair Value Measurements at December 31, 2018
	Quoted Prices in Active Markets For Identical Assets (Level 1)		Significant Other Observable Remaining Inputs (Level 2)			Significant Other Unobservable Remaining Inputs (Level 3)		Total			Quoted Prices in Active Markets For Identical Assets (Level 1)		Significant Other Observable Remaining Inputs (Level 2)			Significant Other Unobservable Remaining Inputs (Level 3)		Total
Assets:
Available-for-sale debt securities:
Asset-backed securities	$	—	$	30.3		$	—	$	30.3		$	—	$	46.5		$	—	$	46.5
Certificates of deposit	—		95.4			—		95.4			—		152.9			—		152.9
Commercial paper	—		377.5			—		377.5			—		393.6			—		393.6
Corporate debt securities	—		362.0			—		362.0			—		413.0			—		413.0
Foreign government debt securities	—		38.3			—		38.3			—		19.9			—		19.9
Time deposits	—		84.2			—		84.2			—		278.6			—		278.6
U.S. government agency securities	—		25.6			—		25.6			—		87.0			—		87.0
U.S. government securities	412.9		333.5			—		746.4			352.8		458.5			—		811.3
Privately-held debt and redeemable preferred stock securities	—		—			52.0		52.0			—		—			54.0		54.0
Total available-for-sale debt securities	412.9		1,346.8			52.0		1,811.7			352.8		1,850.0			54.0		2,256.8
Equity securities:
Money market funds	836.7		—			—		836.7			996.9		—			—		996.9
Mutual funds	26.2		—			—		26.2			24.3		—			—		24.3
Publicly-traded equity securities	1.8		—			—		1.8			2.8		—			—		2.8
Total equity securities	864.7		—			—		864.7			1,024.0		—			—		1,024.0
Derivative assets:
Foreign exchange contracts	—		8.4			—		8.4			—		5.3			—		5.3
Total assets measured at fair value	$	1,277.6	$	1,355.2		$	52.0	$	2,684.8		$	1,376.8	$	1,855.3		$	54.0	$	3,286.1
Liabilities:
Derivative liabilities:
Foreign exchange contracts	$	—	$	(5.8	)	$	—	$	(5.8	)	$	—	$	(7.1	)	$	—	$	(7.1	)
Total liabilities measured at fair value	$	—	$	(5.8	)	$	—	$	(5.8	)	$	—	$	(7.1	)	$	—	$	(7.1	)
Total assets, reported as:
Cash equivalents	$	825.1	$	414.4		$	—	$	1,239.5		$	1,025.2	$	896.6		$	—	$	1,921.8
Short-term investments	406.2		821.2			—		1,227.4			297.5		772.6			—		1,070.1
Long-term investments	8.5		111.2			—		119.7			18.2		180.8			—		199.0
Prepaid expenses and other current assets	11.3		8.4			—		19.7			10.8		5.3			—		16.1
Other long-term assets	26.5		—			52.0		78.5			25.1		—			54.0		79.1
Total assets measured at fair value	$	1,277.6	$	1,355.2		$	52.0	$	2,684.8		$	1,376.8	$	1,855.3		$	54.0	$	3,286.1
Total liabilities, reported as:
Other accrued liabilities	$	—	$	(5.8	)	$	—	$	(5.8	)	$	—	$	(7.1	)	$	—	$	(7.1	)
Total liabilities measured at fair value	$	—	$	(5.8	)	$	—	$	(5.8	)	$	—	$	(7.1	)	$	—	$	(7.1	)