Fair Value Measurements

3 Months Ended

Mar. 31, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair Value Measurements

The Company measures its financial instruments at fair value each reporting period using a fair value hierarchy that prioritizes the use of observable inputs and minimizes the use of unobservable inputs when measuring fair value. A financial instrument’s classification within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

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

The Company had no transfers between levels of the fair value hierarchy.

The carrying amounts of certain financial instruments, including cash held in banks, accounts receivable and accounts payable approximate fair value due to their short-term maturities and are excluded from the fair value table above.