Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2020

Fair Value Disclosures [Abstract]

Summary of assets and liabilities recorded at fair value

The tables below present information about our assets and liabilities that are regularly measured and carried at fair value and indicate the level within the fair value hierarchy of the valuation techniques we utilized to determine such fair value:

	As of September 30, 2020
(In millions)	Total		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents	$	1,570.3	$	—	$	1,570.3	$	—
Marketable debt securities:
Corporate debt securities	1,443.8		—		1,443.8		—
Government securities	767.4		—		767.4		—
Mortgage and other asset backed securities	153.6		—		153.6		—
Marketable equity securities	868.5		276.5		592.0		—
Derivative contracts	26.0		—		26.0		—
Plan assets for deferred compensation	26.4		—		26.4		—
Total	$	4,856.0	$	276.5	$	4,579.5	$	—
Liabilities:
Derivative contracts	$	99.6	$	—	$	99.6	$	—
Contingent consideration obligations	322.6		—		—		322.6
Total	$	422.2	$	—	$	99.6	$	322.6

	As of December 31, 2019
(In millions)	Total		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents	$	2,541.1	$	—	$	2,541.1	$	—
Marketable debt securities:
Corporate debt securities	1,695.1		—		1,695.1		—
Government securities	1,013.9		—		1,013.9		—
Mortgage and other asset backed securities	261.3		—		261.3		—
Marketable equity securities	337.5		7.9		329.6		—
Derivative contracts	43.8		—		43.8		—
Plan assets for deferred compensation	27.7		—		27.7		—
Total	$	5,920.4	$	7.9	$	5,912.5	$	—
Liabilities:
Derivative contracts	$	8.3	$	—	$	8.3	$	—
Contingent consideration obligations	346.1		—		—		346.1
Total	$	354.4	$	—	$	8.3	$	346.1

Summary of fair and carrying value of debt instruments

The fair and carrying values of our debt instruments, which are Level 2 liabilities, are summarized as follows:

	As of September 30, 2020				As of December 31, 2019
(In millions)	Fair Value		Carrying Value		Fair Value		Carrying Value
2.900% Senior Notes due September 15, 2020(1)	$	—	$	—	$	1,509.6	$	1,495.8
3.625% Senior Notes due September 15, 2022	1,058.4		997.5		1,038.9		996.6
4.050% Senior Notes due September 15, 2025	1,988.5		1,740.7		1,897.2		1,739.5
2.250% Senior Notes due May 1, 2030	1,532.8		1,491.0		—		—
5.200% Senior Notes due September 15, 2045	2,286.3		1,723.3		2,107.9		1,722.9
3.150% Senior Notes due May 1, 2050	1,470.0		1,472.5		—		—
Total	$	8,336.0	$	7,425.0	$	6,553.6	$	5,954.8

Fair value of contingent consideration obligations

The following table provides a roll forward of the fair values of our contingent consideration obligations, which includes Level 3 measurements:

	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
(In millions)	2020		2019		2020		2019
Fair value, beginning of period	$	351.6	$	401.3	$	346.1	$	409.8
Changes in fair value	(29.0)		(57.8)		(23.5)		(66.3)
Payments	—		—		—		—
Fair value, end of period	$	322.6	$	343.5	$	322.6	$	343.5