Investments

12 Months Ended

Dec. 31, 2016

Investments, Debt and Equity Securities [Abstract]

Investments

7. Investments

Information regarding our investments is as follows (in millions):

			Gross Unrealized
	Amortized Cost		Gains		Losses			Fair value
As of December 31, 2015
Corporate debt securities	$	245.7	$	0.1	$	(0.4	)	$	245.4
U.S. government and agency debt securities		21.6		–		(0.1	)		21.5
Commercial paper		4.2		–		–			4.2
Certificates of deposit		2.0		–		–			2.0
Total short and long-term investments	$	273.5	$	0.1	$	(0.5	)	$	273.1

In 2016, we either sold or allowed our investments to mature and did not reinvest the cash.