Investments

Available-for-Sale Securities

Available-for-sale investments at April 3, 2016 were as follows:



(in thousands)	Cost			Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
U.S. government treasuries and agencies securities	$	32,374		$	146	$	(1	)	$	32,519
Money market funds	124,504			—		—			124,504
Asset-backed securities	10,518			4		(7		)	10,515
Corporate bonds	91,321			246		(179		)	91,388
International government bonds	2,195			13		—			2,208
Corporate commercial paper	1,992			—		—			1,992
Bank deposits	11,711			—		—			11,711
Repurchase agreements	114			—		—			114
Municipal bonds	900			—		—			900
Total available-for-sale investments	275,629			409		(187		)	275,851
Less amounts classified as cash equivalents	(124,618		)	—		—			(124,618		)
Short-term investments	$	151,011		$	409	$	(187	)	$	151,233

Available-for-sale investments at March 29, 2015 were as follows:



(in thousands)	Cost			Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
U.S. government treasuries and agencies securities	$	135,570		$	398	$	(23	)	$	135,945
Money market funds	55,578			—		—			55,578
Asset-backed securities	31,830			9		(9		)	31,830
Corporate bonds	245,229			567		(121		)	245,675
International government bonds	1,010			—		(4		)	1,006
Corporate commercial paper	4,999			—		—			4,999
Bank deposits	16,915			—		—			16,915
Repurchase agreements	191			—		—			191
Municipal bonds	6,001			45		(2		)	6,044
Total available-for-sale investments	497,323			1,019		(159		)	498,183
Less amounts classified as cash equivalents	(60,068		)	—		—			(60,068		)
Short-term investments	$	437,255		$	1,019	$	(159	)	$	438,115

The cost and estimated fair value of available-for-sale debt securities at April 3, 2016, by contractual maturity, were as follows:



(in thousands)	Amortized Cost		Estimated Fair Value
Due in 1 year or less	$	150,253	$	150,262
Due in 1-2 years	69,571		69,666
Due in 2-5 years	55,805		55,923
Total investments in available-for-sale debt securities	$	275,629	$	275,851

The cost and estimated fair value of available-for-sale debt securities at March 29, 2015, by contractual maturity, were as follows:



(in thousands)	Amortized Cost		Estimated Fair Value
Due in 1 year or less	$	153,753	$	153,823
Due in 1-2 years	132,241		132,529
Due in 2-5 years	211,329		211,831
Total investments in available-for-sale debt securities	$	497,323	$	498,183

The following table shows the gross unrealized losses and fair value of the Company’s investments with unrealized losses as of April 3, 2016, aggregated by investment category and length of time that individual securities have been in a continuous loss position.



	Less Than 12 Months					12 Months or Greater				Total
(in thousands)	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Corporate bonds	$	33,407	$	(179	)	$	—	$	—	$	33,407	$	(179	)
Asset-backed securities	4,979		(7		)	—		—		4,979		(7		)
U.S. government treasuries and agencies securities	6,097		(1		)	—		—		6,097		(1		)
Total	$	44,483	$	(187	)	$	—	$	—	$	44,483	$	(187	)

The following table shows the gross unrealized losses and fair value of the Company’s investments with unrealized losses, as of March 29, 2015, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position.



	Less Than 12 Months					12 Months or Greater				Total
(in thousands)	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Corporate bonds	$	63,367	$	(121	)	$	—	$	—	$	63,367	$	(121	)
Asset-backed securities	17,736		(9		)					17,736		(9		)
U.S. government treasuries and agencies securities	18,478		(23		)	—		—		18,478		(23		)
Municipal bonds	1,001		(2		)	—		—		1,001		(2		)
International government bonds	1,006		(4		)	—		—		1,006		(4		)
Total	$	101,588	$	(159	)	$	—	$	—	$	101,588	$	(159	)

Currently, a significant portion of the Company’s available-for-sale investments that it holds are high grade instruments. As of April 3, 2016, the unrealized losses on the Company’s available-for-sale investments represented an insignificant amount in relation to its total available-for-sale portfolio. Substantially all of the Company’s unrealized losses on its available-for-sale marketable debt instruments can be attributed to fair value fluctuations in an unstable credit environment that resulted in a decrease in the market liquidity for debt instruments. Because the Company has the ability to hold these investments until a recovery of fair value, which may be maturity, the Company did not consider these investments to be other-than-temporarily impaired at April 3, 2016 or March 29, 2015.

Non-marketable Equity Securities

The Company accounts for its equity investments in privately held companies under the cost method. These investments are subject to periodic impairment review and measured and recorded at fair value when they are deemed to be other-than-temporarily impaired. In determining whether a decline in value of its investment has occurred and is other than temporary, an assessment was made by considering available evidence, including the general market conditions, the investee’s financial condition, near-term prospects, market comparables and subsequent rounds of financing. The valuation also takes into account the investee’s capital structure, liquidation preferences for its capital and other economic variables. The valuation methodology for determining the decline in value of non-marketable equity securities is based on inputs that require management's judgment.

As of April 3, 2016 and March 29, 2015, the Company holds capital stock of privately-held companies with total amount of $10.0 million and $4.0 million, respectively. During fiscal 2016, the Company purchased $2.0 million of convertible notes in a privately-held company which were automatically converted into ordinary shares of stock in accordance with the terms of the instrument at December 31, 2015. During fiscal 2016, the Company also purchased preferred shares of a privately-held company for $4.0 million. These and other investments in stocks (included in Other Assets on the Consolidated Balance Sheet) are accounted for as cost-method investments, as the Company owns less than 20% of the voting securities and does not have the ability to exercise significant influence over operating and financial policies of the entity.

The Company did not record any impairment charge for these investments in fiscal 2016, 2015 and 2014.