Investments

6 Months Ended

Jun. 30, 2016

Investments, Debt and Equity Securities [Abstract]

Investments

6. Investments

We invest in short and long-term investments classified as available-for-sale securities. Information regarding our investments is as follows (in millions):

	Amortized Cost		Gross Unrealized
			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

During the three months ended June 30, 2016, we sold all of our short and long-term investments for $49.8 million in proceeds. The realized gain/loss on these sales was minimal.