Marketable Securities and Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2015

Investments, All Other Investments [Abstract]

Short-Term And Long-Term Marketable Securities

As of December 31, 2015 and 2014, the estimated fair value of our short-term and long-term investments, classified as available for sale, are as follows (in thousands):

Short-term

December 31, 2015	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial paper	$	38,537	$	—	$	—		$	38,537
Corporate bonds	179,765		6		(251		)	179,520
U.S. dollar dominated foreign corporate bonds	510		—		(2		)	508
Municipal securities	14,209		7		(2		)	14,214
U.S. government agency bonds	75,172		—		(53		)	75,119
U.S. government treasury bonds	51,763		1		(81		)	51,683
Total Marketable Securities, Short-Term	$	359,956	$	14	$	(389	)	$	359,581

Long-term

December 31, 2015	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
U.S. government agency bonds	$	43,853	$	—	$	(178	)	$	43,675
Corporate bonds	64,012		9		(217		)	63,804
U.S. government treasury bonds	37,673		—		(107		)	37,566
Municipal securities	3,993		—		(2		)	3,991
Asset-backed securities	2,338		—		(3		)	2,335
Total Marketable Securities, Long-Term	$	151,869	$	9	$	(507	)	$	151,371

Short-term

December 31, 2014	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Commercial paper	$	33,998	$	—	$	—		$	33,998
Corporate bonds	152,055		27		(116		)	151,966
U.S. dollar dominated foreign corporate bonds	901		—		—			901
Municipal securities	9,147		13		—			9,160
U.S. government agency bonds	41,574		14		(1		)	41,587
U.S.government treasury bonds	15,770		7		—			15,777
Asset-backed securities	1,398		—		—			1,398
Total Marketable Securities, Short-Term	$	254,843	$	61	$	(117	)	$	254,787

Long-term

December 31, 2014	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
U.S. government agency bonds	$	48,233	$	12	$	(28	)	$	48,217
Corporate bonds	57,195		6		(112		)	57,089
U.S. dollar dominated foreign corporate bonds	523		—		(2		)	521
U.S. government treasury bonds	20,814		5		(6		)	20,813
Municipal securities	9,552		5		(6		)	9,551
Asset-backed securities	11,713		—		(12		)	11,701
Total Marketable Securities, Long-Term	$	148,030	$	28	$	(166	)	$	147,892

Marketable Securities

As the carrying value approximates the fair value for our short-term and long-term marketable securities shown in the tables above, the following table summarizes the fair value of our short-term and long-term marketable securities classified by maturity as of December 31, 2015 and 2014  (in thousands):

	December 31,		December 31,
	2015		2014
One year or less	$	359,581	$	254,787
Due in greater than one year	151,370		147,892
Total available for short-term and long-term marketable securities	$	510,951	$	402,679

Financial Assets Measured At Fair Value On A Recurring Basis

The following tables summarizes our financial assets measured at fair value on a recurring basis as of December 31, 2015 and 2014 (in thousands):

Description	Balance as of December 31, 2015		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
Cash equivalents:
Money market funds	$	70,148	$	70,148	$	—
Commercial paper	36,887		—		36,887
U.S. government Agency bonds	3,599				3,599
Corporate bonds	625		—		625
Short-term investments:
Commercial paper	38,537		—		38,537
Corporate bonds	179,520		—		179,520
U.S. dollar denominated foreign corporate bonds	508		—		508
Municipal securities	14,214		—		14,214
U.S. government agency bonds	75,119		—		75,119
U.S. government treasury bonds	51,683		51,683		—
Long-term investments:
Corporate bonds	63,804		—		63,804
U.S. government agency bonds	43,675		—		43,675
U.S. government treasury bonds	37,566		37,566		—
Municipal securities	3,991		—		3,991
Asset-backed securities	2,335		—		2,335
Long-term other assets:
Israeli funds	2,436		—		2,436
	$	624,647	$	159,397	$	465,250

Description	Balance as of December 31, 2014		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
Cash equivalents:
Money market funds	$	80,786	$	80,786	$	—
Commercial paper	21,997		—		21,997
Corporate bonds	1,745				1,745
Short-term investments:
Commercial paper	33,998		—		33,998
Corporate bonds	151,966		—		151,966
U.S. dollar denominated foreign corporate bonds	901		—		901
Municipal securities	9,160		—		9,160
U.S. government agency bonds	41,587		—		41,587
U.S. government treasury bonds	15,777		15,777		—
Certificate of Deposits	1,398				1,398
Long-term investments:
Corporate bonds	57,089		—		57,089
U.S. government agency bonds	48,217		—		48,217
U.S. dollar denominated foreign corporate bonds	521		—		521
U.S. government treasury bonds	20,813		20,813		—
Municipal securities	9,551		—		9,551
Asset-backed securities	11,701		—		11,701
Long-term other assets:
Israeli funds	2,307		—		2,307
	$	509,514	$	117,376	$	392,138

Schedule of Notional Amounts of Outstanding Derivative Positions

The following table presents the gross notional value of all our foreign exchange forward contracts outstanding as of December 31, 2015 (in thousands):

	As of December 31, 2015
	Local Currency Amount		Notional Contract Amount (USD)
US dollar	$	20,700	$	20,700
Euro	€22,100		24,222
Japanese yen	¥583,000		4,839
Australian dollar	A$4,700		3,426
Hong Kong dollar	HK$	51,000	6,579
			$	59,766