Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2020

Fair Value Disclosures [Abstract]

Schedule of fair value assets measured on recurring basis

The following table presents information about the Company’s financial instruments that are measured at fair value on a recurring basis using the input categories discussed in Note 1:   

	As of March 31, 2020
	Level 1		Level 2		Level 3		Total
Cash equivalents
Money market funds	$	373.0	$	—	$	—	$	373.0
Commercial paper	—		1.3		—		1.3
Total cash equivalents	$	373.0	$	1.3	$	—	$	374.3
Short-term investments
Corporate notes and obligations	—		286.9		—		286.9
U.S. Treasury securities	—		175.4		—		175.4
Asset backed securities	—		58.5		—		58.5
Certificates of deposit	—		30.8		—		30.8
Commercial paper	—		21.4		—		21.4
Equity securities	20.6		—		—		20.6
U.S agency obligations	—		15.5		—		15.5
Supranational securities	—		2.8		—		2.8
Municipal securities	—		2.5		—		2.5
Total short-term investments	$	20.6	$	593.8	$	—	$	614.4
Total cash equivalents and short-term investments	$	393.6	$	595.1	$	—	$	988.7

	As of December 31, 2019
	Level 1		Level 2		Level 3		Total
Cash equivalents
Money market funds	$	444.3	$	—	$	—	$	444.3
Commercial paper	—		2.0		—		2.0
Total Cash Equivalents	$	444.3	$	2.0	$	—	$	446.3
Short-term investments
Corporate notes and obligations	—		286.6		—		286.6
U.S. Treasury securities	—		171.3		—		171.3
Asset-backed securities	—		53.8		—		53.8
Certificates of deposit	—		38.2		—		38.2
U.S. agency obligations	—		27.2		—		27.2
Commercial paper	—		24.2		—		24.2
Supranational securities	—		4.0		—		4.0
Municipal securities	—		2.4		—		2.4
Total short-term investments	$	—	$	607.7	$	—	$	607.7
Equity Investments	9.8		—		—		9.8
Total	$	454.1	$	609.7	$	—	$	1,063.8