Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2017

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 June 30, 2017 Using:										Fair Value Measurements at December 31, 2016 Using:
	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 securities:
Asset-backed securities	$	—	$	309.3		$	—	$	309.3		$	—	$	303.0		$	—	$	303.0
Certificates of deposit	—		45.7			—		45.7			—		66.1			—		66.1
Commercial paper	—		167.8			—		167.8			—		147.7			—		147.7
Corporate debt securities	—		863.1			—		863.1			—		844.9			—		844.9
Foreign government debt securities	—		43.9			—		43.9			—		33.9			—		33.9
Money market funds	1,206.6		—			—		1,206.6			592.2		—			—		592.2
Mutual funds	8.3		—			—		8.3			8.0		—			—		8.0
Publicly-traded equity securities	5.3		—			—		5.3			4.6		—			—		4.6
Time deposits	—		290.7			—		290.7			—		264.6			—		264.6
U.S. government agency securities	—		163.0			—		163.0			—		126.7			—		126.7
U.S. government securities	337.1		21.6			—		358.7			345.0		45.4			—		390.4
Total available-for-sale securities	1,557.3		1,905.1			—		3,462.4			949.8		1,832.3			—		2,782.1
Trading securities in mutual funds	23.9		—			—		23.9			21.0		—			—		21.0
Privately-held debt and redeemable preferred stock securities	—		—			42.3		42.3			—		—			43.7		43.7
Derivative assets:
Foreign exchange contracts	—		5.8			—		5.8			—		0.9			—		0.9
Total assets measured at fair value	$	1,581.2	$	1,910.9		$	42.3	$	3,534.4		$	970.8	$	1,833.2		$	43.7	$	2,847.7
Liabilities:
Derivative liabilities:
Foreign exchange contracts	$	—	$	(0.6	)	$	—	$	(0.6	)	$	—	$	(4.9	)	$	—	$	(4.9	)
Total liabilities measured at fair value	$	—	$	(0.6	)	$	—	$	(0.6	)	$	—	$	(4.9	)	$	—	$	(4.9	)
Total assets, reported as:
Cash equivalents	$	1,168.4	$	420.8		$	—	$	1,589.2		$	549.4	$	357.7		$	—	$	907.1
Restricted investments	75.0		—			—		75.0			71.9		—			—		71.9
Short-term investments	194.8		557.9			—		752.7			178.0		574.3			—		752.3
Long-term investments	143.0		926.4			—		1,069.4			171.5		900.3			—		1,071.8
Prepaid expenses and other current assets	—		5.8			—		5.8			—		0.9			—		0.9
Other long-term assets	—		—			42.3		42.3			—		—			43.7		43.7
Total assets measured at fair value	$	1,581.2	$	1,910.9		$	42.3	$	3,534.4		$	970.8	$	1,833.2		$	43.7	$	2,847.7
Total liabilities, reported as:
Other accrued liabilities	$	—	$	(0.6	)	$	—	$	(0.6	)	$	—	$	(4.9	)	$	—	$	(4.9	)
Total liabilities measured at fair value	$	—	$	(0.6	)	$	—	$	(0.6	)	$	—	$	(4.9	)	$	—	$	(4.9	)