Cash, Cash Equivalents and Short-Term Investments (Tables)

6 Months Ended

Jun. 30, 2020

Cash and Cash Equivalents [Abstract]

Schedule of Cash, Cash Equivalents and Short-Term Investments

The amortized cost, unrealized gains and losses and estimated fair value of the Company's cash, cash equivalents and short-term investments as of June 30, 2020 and December 31, 2019 consisted of the following:

	As of June 30, 2020
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Cash	$	88.5	$	—	$	—		$	88.5
Cash equivalents
Money market funds	241.6		—		(0.1		)	241.5
Municipal securities	1.8		—		—			1.8
Commercial paper	1.2		—		—			1.2
Corporate notes and obligations	1.1		—		—			1.1
Total cash and cash equivalents	$	334.2	$	—	$	(0.1	)	$	334.1
Short-term investments
Corporate notes and obligations	358.3		3.3		(0.2		)	361.4
U.S. Treasury securities	234.1		1.7		—			235.8
Asset backed securities	83.0		0.7		(0.1		)	83.6
Commercial paper	40.0		—		—			40.0
U.S. agency obligations	27.8		0.1		—			27.9
Certificates of deposit	26.0		—		—			26.0
Municipal securities	5.9		0.1		—			6.0
Foreign government obligations	2.8		—		—			2.8
Total short-term investments	777.9		5.9		(0.3		)	783.5
Total	$	1,112.1	$	5.9	$	(0.4	)	$	1,117.6

	As of December 31, 2019
	Amortized cost		Unrealized gain		Unrealized loss			Estimated fair value
Cash	$	105.0	$	—	$	—		$	105.0
Cash equivalents:
Money market funds	444.3		—		—			444.3
Commercial paper	2.0		—		—			2.0
Total cash and cash equivalents	$	551.3	$	—	$	—		$	551.3
Short-term investments								—
Corporate notes and obligations	285.5		1.2		(0.1		)	286.6
U.S. Treasury securities	171.0		0.3		—			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	606.3		1.5		(0.1		)	607.7
Total	$	1,157.6	$	1.5	$	(0.1	)	$	1,159.0

Contractual Maturities of Short Term Investments

The following table presents the contractual maturities of the Company’s short-term investments as of June 30, 2020:

	As of June 30, 2020
	Amortized cost		Estimated fair value
Due within one year	434.1		435.7
Due between one to three years	304.2		307.9
Due after three years	39.6		39.9
Total	$	777.9	$	783.5