Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Financial assets subject to fair value measurements (excluding VIE cash and cash equivalents, which are recorded as Restricted cash and cash equivalents (VIE))

The following table sets forth the Company’s financial assets and liabilities subject to fair value measurements (and does not include $1.5 billion and $1.4 billion of cash as of March 31, 2019 and December 31, 2018, respectively):

	Fair Value Measurements as of March 31, 2019
				Fair Value Hierarchy
	Total			Level 1		Level 2			Level 3
	(in thousands)
Financial instruments carried at fair value (asset positions):
Cash equivalents:
Money market funds	$	1,354,656		$	1,354,656	$	—		$	—
U.S. Treasury securities	5,996			5,996		—			—
Government-sponsored enterprise securities	11,786			11,786		—			—
Corporate debt securities	4,519			—		4,519			—
Commercial paper	35,955			—		35,955			—
Marketable securities:
Corporate equity securities	210,874			192,207		18,667			—
Government-sponsored enterprise securities	15,181			15,181		—			—
Corporate debt securities	231,572			—		231,572			—
Commercial paper	126,523			—		126,523			—
Prepaid expenses and other current assets:
Foreign currency forward contracts	19,210			—		19,210			—
Other assets:
Foreign currency forward contracts	973			—		973			—
Total financial assets	$	2,017,245		$	1,579,826	$	437,419		$	—
Financial instruments carried at fair value (liability positions):
Other current liabilities:
Foreign currency forward contracts	$	(310	)	$	—	$	(310	)	$	—
Other long-term liabilities:
Foreign currency forward contracts	(68		)	—		(68		)	—
Total financial liabilities	$	(378	)	$	—	$	(378	)	$	—

	Fair Value Measurements as of December 31, 2018
				Fair Value Hierarchy
	Total			Level 1		Level 2			Level 3
	(in thousands)
Financial instruments carried at fair value (asset positions):
Cash equivalents:
Money market funds	$	1,226,603		$	1,226,603	$	—		$	—
U.S. Treasury securities	5,966			5,966		—			—
Government-sponsored enterprise securities	7,123			7,123		—			—
Commercial paper	58,268			—		58,268			—
Marketable securities:
Corporate equity securities	167,323			153,733		13,590			—
U.S. Treasury securities	6,026			6,026		—			—
Government-sponsored enterprise securities	10,704			10,704		—			—
Corporate debt securities	233,665			—		233,665			—
Commercial paper	100,390			—		100,390			—
Prepaid expenses and other current assets:
Foreign currency forward contracts	19,023			—		19,023			—
Other assets:
Foreign currency forward contracts	1,514			—		1,514			—
Total financial assets	$	1,836,605		$	1,410,155	$	426,450		$	—
Financial instruments carried at fair value (liability positions):
Other current liabilities:
Foreign currency forward contracts	$	(340	)	$	—	$	(340	)	$	—
Other long-term liabilities:
Foreign currency forward contracts	(108		)	—		(108		)	—
Total financial liabilities	$	(448	)	$	—	$	(448	)	$	—