Investments (Tables)

9 Months Ended

Sep. 30, 2020

Investments, Debt and Equity Securities [Abstract]

Summary of Amortized Cost, Gross Unrealized Gains and Losses, Fair Value and Level in Fair Value Hierarchy for Investments

The following table provides amortized costs, gross unrealized gains and losses, fair values and the level in the fair value hierarchy for the Company’s investments at September 30, 2020 and December 31, 2019:

(in millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		Level 1		Level 2 (1)
September 30, 2020
U.S. government and agency bonds	$	52.7	$	0.4	$	—	$	53.1	$	53.1	$	—
Corporate bonds	2.8		—		—		2.8		—		2.8
Certificates of deposit	2.7		—		—		2.7		—		2.7
Total short-term investments	$	58.2	$	0.4	$	—	$	58.6	$	53.1	$	5.5
Certificates of deposit	$	0.5	$	—	$	—	$	0.5	$	—	$	0.5
Total long-term investments	$	0.5	$	—	$	—	$	0.5	$	—	$	0.5
December 31, 2019
U.S. government and agency bonds	$	94.7	$	0.3	$	—	$	95.0	$	85.0	$	10.0
Corporate bonds	51.0		0.1		—		51.1		—		51.1
Certificates of deposit	6.3		—		—		6.3		—		6.3
Commercial Paper	10.0		—		—		10.0		—		10.0
Total short-term investments	$	162.0	$	0.4	$	—	$	162.4	$	85.0	$	77.4
U.S. government and agency bonds	$	52.9	$	0.1	$	(0.1)	$	52.9	$	42.9	$	10.0
Corporate bonds	2.8		—		—		2.8		—		2.8
Certificates of deposit	2.7		—		—		2.7		—		2.7
Total long-term investments	$	58.4	$	0.1	$	(0.1)	$	58.4	$	42.9	$	15.5

(1) Fair value was determined using market prices obtained from third-party pricing sources.