INVESTMENTS

12 Months Ended

Dec. 31, 2015

Investments Schedule [Abstract]

INVESTMENTS

NOTE 3. INVESTMENTS

Available-for-sale securities are carried at fair value, with the unrealized gains and losses reported in comprehensive loss. The amortized cost of debt securities in this category is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion is included in investment income. Realized gains and losses and declines in value judged to be other-than-temporary, if any, on available-for-sale securities are included in other income or expense. The cost of securities sold is based on the specific identification method. Interest and dividends on securities classified as available-for-sale are included in investment income.

Investments at December 31, 2015 and 2014 consisted of the following (in thousands):

	Years Ended December 31,
	2015		2014
Certificates of deposit	$	10,078	$	17,438
Commercial paper		23,955		7,498
Corporate debt securities		323,219		174,323
Securities of government-sponsored entities		30,232		1,028
Total investments	$	387,484	$	200,287

The following is a summary of investments classified as available-for-sale securities (in thousands):

	Contractual Maturity (in years)	Amortized Cost		Gross Unrealized Gains(1)		Gross Unrealized Losses(1)			Aggregate Estimated Fair Value
December 31, 2015:
Classified as current assets:
Certificates of deposit	Less than 1	$	9,120	$	1	$	(1	)	$	9,120
Commercial paper	Less than 1		23,965		1		(11	)		23,955
Corporate debt securities	Less than 1		254,592		1		(414	)		254,179
Securities of government-sponsored entities	Less than 1		17,762		1		(21	)		17,742
Total short-term available-for-sale securities		$	305,439	$	4	$	(447	)	$	304,996
Classified as non-current assets:
Certificates of deposit	1 to 2	$	960	$	—	$	(2	)	$	958
Corporate debt securities	1 to 2		69,528		—		(488	)		69,040
Securities of government-sponsored entities	1 to 2		12,534		—		(44	)		12,490
Total long-term available-for-sale securities		$	83,022	$	—	$	(534	)	$	82,488
December 31, 2014:
Classified as current assets:
Certificates of deposit	Less than 1	$	9,072	$	—	$	(6	)	$	9,066
Commercial paper	Less than 1		7,497		1		—			7,498
Corporate debt securities	Less than 1		145,321		5		(123	)		145,203
Securities of government-sponsored entities	Less than 1		1,029		—		(1	)		1,028
Total short-term available-for-sale securities		$	162,919	$	6	$	(130	)	$	162,795
Classified as non-current assets:
Certificates of deposit	1 to 2	$	8,400	$	—	$	(28	)	$	8,372
Corporate debt securities	1 to 2		29,245		—		(125	)		29,120
Total long-term available-for-sale securities		$	37,645	$	—	$	(153	)	$	37,492

(1) Unrealized gains and losses are included in other comprehensive loss.

The following table presents gross unrealized losses and fair value for those available-for-sale investments that were in an unrealized loss position as of December 31, 2015 and 2014, aggregated by investment category and length of time that individual securities have been in a continuous loss position (in thousands):

	Less Than 12 Months					12 Months or Greater					Total
	Estimated Fair Value		Unrealized Losses			Estimated Fair Value		Unrealized Losses			Estimated Fair Value		Unrealized Losses
December 31, 2015:
Certificates of deposit	$	5,517	$	(3	)	$	—	$	—		$	5,517	$	(3	)
Commercial paper		16,959		(11	)		—		—			16,959		(11	)
Corporate debt securities		310,160		(880	)		5,521		(22	)		315,681		(902	)
Securities of government-sponsored entities		25,913		(65	)		—		—			25,913		(65	)
Total	$	358,549	$	(959	)	$	5,521	$	(22	)	$	364,070	$	(981	)
December 31, 2014:
Certificates of deposit	$	16,957	$	(34	)	$	—	$	—		$	16,957	$	(34	)
Corporate debt securities		149,477		(248	)		—		—			149,477		(248	)
Securities of government-sponsored entities		1,028		(1	)		—		—			1,028		(1	)
Total	$	167,462	$	(283	)	$	—	$	—		$	167,462	$	(283	)