Investments

Short-term and long-term investments consist of high-grade corporate bonds and other debt securities. All marketable investments are classified as available-for-sale as of June 24, 2012.

The following table provides a summary of marketable investments as of June 24, 2012 (in thousands):



	June 24, 2012
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Municipal bonds	$	209,626	$	2,036	$	(58	)	$	211,604
Corporate bonds	144,942		1,848		(123		)	146,667
Municipal variable rate demand notes	—		—		—			—
U.S. agency securities	68,156		450		(7		)	68,599
Certificates of deposit	130,000		—		—			130,000
Commercial paper	—		—		—			—
Non-U.S. government securities	8,746		15		(3		)	8,758
Total	$	561,470	$	4,349	$	(191	)	$	565,628

The following table presents the gross unrealized losses and estimated fair value of the Company’s investment securities, aggregated by investment type and the length of time that individual investment securities have been in a continuous unrealized loss position, as of June 24, 2012 (in thousands):



	June 24, 2012
	Less than 12 Months					Greater than 12 Months				Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Municipal bonds	$	30,102	$	(58	)	$	—	$	—	$	30,102	$	(58	)
Corporate bonds	30,550		(123		)	—		—		30,550		(123		)
Municipal variable rate demand notes	—		—			—		—		—		—
U.S. agency securities	3,014		(7		)	—		—		3,014		(7		)
Certificates of deposit	—		—			—		—		—		—
Commercial paper	—		—			—		—		—		—
Non-U.S. government securities	1,543		(3		)	—		—		1,543		(3		)
Total	$	65,209	$	(191	)	$	—	$	—	$	65,209	$	(191	)
Number of securities with an unrealized loss			33					—				33

The following table provides a summary of marketable investments as of June 26, 2011 (in thousands):



	June 26, 2011
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Municipal bonds	$	391,465	$	3,943	$	(10	)	$	395,398
Corporate bonds	207,241		2,312		(115		)	209,438
Municipal variable rate demand notes	295		—		—			295
U.S. agency securities	67,244		807		(2		)	68,049
Certificates of deposit	10,003		12		—			10,015
Commercial paper	4,999		—		—			4,999
Non-U.S. government securities	6,986		19		—			7,005
Total	$	688,233	$	7,093	$	(127	)	$	695,199



	June 26, 2011
	Less than 12 Months					Greater than 12 Months				Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Municipal bonds	$	14,348	$	(10	)	$	—	$	—	$	14,348	$	(10	)
Corporate bonds	20,484		(115		)	—		—		20,484		(115		)
Municipal variable rate demand notes	—		—			—		—		—		—
U.S. agency securities	6,518		(2		)	—		—		6,518		(2		)
Certificates of deposit	—		—			—		—		—		—
Commercial paper	—		—			—		—		—		—
Non-U.S. government securities	—		—			—		—		—		—
Total	$	41,350	$	(127	)	$	—	$	—	$	41,350	$	(127	)
Number of securities with an unrealized loss			20					—				20

Each of the securities in the above tables generally has an investment grade rating and is an unrealized loss position solely due to interest rate changes, sector credit rating changes or company-specific rating changes. The Company evaluates its investments for possible impairment or a decline in fair value below cost basis that is deemed to be “other than temporary” on a periodic basis. It considers such factors as the length of time and extent to which the fair value has been below the cost basis, the financial condition of the investee, and its ability and intent to hold the investment for a period of time that may be sufficient for an anticipated full recovery in market value. Accordingly, the Company considers declines in its securities to be temporary in nature, and does not consider its securities to be impaired as of June 24, 2012 and June 26, 2011.

The contractual maturities of marketable investments at June 24, 2012 were as follows (in thousands):



	Within One Year		After One, Within Five Years		After Five, Within Ten Years		After Ten Years		Total
Municipal bonds	$	85,261	$	126,343	$	—	$	—	$	211,604
Corporate bonds	50,462		92,221		3,984		—		146,667
Municipal variable rate demand notes	—		—		—		—		—
U.S. agency securities	31,856		36,743		—		—		68,599
Certificates of deposit	130,000		—		—		—		130,000
Commercial paper	—		—		—		—		—
Non-U.S. government securities	4,559		4,199		—		—		8,758
Total	$	302,138	$	259,506	$	3,984	$	—	$	565,628