Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2015

Fair Value Disclosures [Abstract]

Financial assets subject to fair value measurements (excluding restricted cash and cash equivalents (VIE))

The following table sets forth the Company’s financial assets (excluding VIE cash and cash equivalents) subject to fair value measurements:

	Fair Value Measurements as of December 31, 2015
				Fair Value Hierarchy
	Total			Level 1		Level 2			Level 3
	(in thousands)
Financial instruments carried at fair value (asset position):
Cash equivalents:
Money market funds	$	199,507		$	199,507	$	—		$	—
Government-sponsored enterprise securities	85,994			85,994		—			—
Commercial paper	34,889			—		34,889			—
Corporate debt securities	11,533			—		11,533			—
Marketable securities:
Government-sponsored enterprise securities	87,162			87,162		—			—
Commercial paper	141,409			—		141,409			—
Corporate debt securities	99,123			—		99,123			—
Prepaid and other current assets:
Foreign currency forward contracts	5,161			—		5,161			—
Other assets:
Foreign currency forward contracts	605			$	—	605			$	—
Total financial assets	$	665,383		$	372,663	$	292,720		$	—
Financial instruments carried at fair value (liability position):
Other liabilities, current portion:
Foreign currency forward contracts	$	(769	)	$	—	$	(769	)	$	—
Other liabilities, excluding current portion:
Foreign currency forward contracts	(132		)	—		(132		)	—
Total financial liabilities	$	(901	)	$	—	$	(901	)	$	—

	Fair Value Measurements as of December 31, 2014
			Fair Value Hierarchy
	Total		Level 1		Level 2		Level 3
	(in thousands)
Financial instruments carried at fair value (asset position):
Cash equivalents:
Money market funds	$	290,531	$	290,531	$	—	$	—
Marketable securities:
Government-sponsored enterprise securities	463,750		463,750		—		—
Commercial paper	51,746		—		51,746		—
Corporate debt securities	246,351		—		246,351		—
Prepaid and other current assets:
Foreign currency forward contracts	2,011		—		2,011		—
Total	$	1,054,389	$	754,281	$	300,108	$	—