Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2020

Investments Measured at Fair Value on Recurring Basis

Investments at September 30, 2020, which were measured at fair value on a recurring basis, consisted of the following:


			Fair Value Measurements Using
(in millions)	Fair Value		Level 1		Level 2		Level 3
Cash and cash equivalents:
Cash and money market funds	$	425.3	$	425.3	$	—	$	—
Total cash and cash equivalents	425.3		425.3		—		—
Restricted cash:
Certificates of deposit	3.2		3.2		—		—
Total restricted cash	3.2		3.2		—		—
Debt securities available-for-sale:
Commercial paper	104.8		—		104.8		—
Corporate debt securities	429.2		—		429.2		—
Securities of government-sponsored entities	166.8		—		166.8		—
Total debt securities available-for-sale	700.8		—		700.8		—
Equity securities:
Equity securities–biotechnology industry	43.7		—		—		43.7
Total equity securities	43.7		—		—		43.7
Total recurring fair value measurements	$	1,173.0	$	428.5	$	700.8	$	43.7

Investments at December 31, 2019, which were measured at fair value on a recurring basis, consisted of the following:


			Fair Value Measurements Using
(in millions)	Fair Value		Level 1		Level 2		Level 3
Cash and cash equivalents:
Cash and money market funds	$	112.3	$	112.3	—		—
Total cash and cash equivalents	112.3		112.3		—		—
Restricted cash:
Certificates of deposit	3.2		3.2		—		—
Total restricted cash	3.2		3.2		—		—
Debt securities available-for-sale:
Commercial paper	144.5		—		144.5		—
Corporate debt securities	521.9		—		521.9		—
Securities of government-sponsored entities	191.5		—		191.5		—
Total debt securities available-for-sale	857.9		—		857.9		—
Equity securities:
Equity securities–biotechnology industry	55.9		—		—		55.9
Total equity securities	55.9		—		—		55.9
Total recurring fair value measurements	$	1,029.3	$	115.5	$	857.9	$	55.9

Reconciliation of Our Investment in Restricted Equity Securities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3)

The following table presents a reconciliation of equity security investments, which were measured at fair value on a recurring basis using significant unobservable inputs (Level 3):


	Three Months Ended September 30,				Nine Months Ended September 30,
(in millions)	2020		2019		2020		2019
Balance at beginning of period	$	50.7	$	77.4	$	55.9	$	—
Purchases	—		—		—		54.7
Unrealized loss included in earnings	(7.0)		(28.5)		(12.2)		(5.8)
Balance at end of period	$	43.7	$	48.9	$	43.7	$	48.9