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

6 Months Ended

Jun. 30, 2015

Cash and Cash Equivalents [Abstract]

Summary of Cash, Cash Equivalents, and Short-Term Investments

The following table summarizes the Company’s cash, cash equivalents, and short-term investments at June 30, 2015 and December 31, 2014:

	Amortized		Gross Unrealized					Fair
	Cost		Gains		Losses			Value
June 30, 2015
Cash and cash equivalents:
Cash	$	224,412	$	—	$	—		$	224,412
Money market funds		189,041		—		—			189,041
Commercial paper		7,697		—		—			7,697
Total cash and cash equivalents		421,150		—		—			421,150
Short-term investments:
Corporate debt securities		42,830		1		(39	)		42,792
Commercial paper		21,568		—		—			21,568
Federal agency securities		9,993		4		—			9,997
Certificates of deposit		2,000		—		—			2,000
Total short-term investments		76,391		5		(39	)		76,357
Total cash, cash equivalents, and short-term investments	$	497,541	$	5	$	(39	)	$	497,507

	Amortized		Gross Unrealized				Fair
	Cost		Gains		Losses		Value
December 31, 2014
Cash and cash equivalents:
Cash	$	313,646	$	—	$	—	$	313,646
Money market funds		189,031		—		—		189,031
Total cash and cash equivalents	$	502,677	$	—	$	—	$	502,677