CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS

Cash equivalents consist of instruments with remaining maturities of three months or less at the date of purchase. We classify all of our cash equivalents and short-term investments as “available-for-sale.” In general, these investments are free of trading restrictions. We carry these investments at fair value, based on quoted market prices or other readily available market information. Unrealized gains and losses, net of taxes, are included in accumulated other comprehensive income, which is reflected as a separate component of stockholders’ equity in our Consolidated Balance Sheets. Gains and losses are recognized when realized in our Consolidated Statements of Income. When we have determined that an other-than-temporary decline in fair value has occurred, the amount of the decline that is related to a credit loss is recognized in income. Gains and losses are determined using the specific identification method.

Cash, cash equivalents and short-term investments consisted of the following as of December 2, 2011 (in thousands):



	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Current assets:
Cash	$	261,206	$	—	$	—		$	261,206
Cash equivalents:
Corporate bonds and commercial paper	15,948		—		—			15,948
Money market mutual funds and repurchase agreements	687,152		—		—			687,152
Time deposits	15,694		—		—			15,694
U.S. agency securities	2,500		—		—			2,500
U.S. Treasury securities	7,000		—		—			7,000
Total cash equivalents	728,294		—		—			728,294
Total cash and cash equivalents	989,500		—		—			989,500
Short-term fixed income securities:
Corporate bonds and commercial paper	1,109,674		6,533		(4,670		)	1,111,537
Foreign government securities	7,280		43		—			7,323
Municipal securities	106,255		104		(4		)	106,355
U.S. agency securities	374,514		1,496		(117		)	375,893
U.S. Treasury securities	307,181		1,640		(4		)	308,817
Subtotal	1,904,904		9,816		(4,795		)	1,909,925
Marketable equity securities	10,581		1,686		—			12,267
Total short-term investments	1,915,485		11,502		(4,795		)	1,922,192
Total cash, cash equivalents and short-term investments	$	2,904,985	$	11,502	$	(4,795	)	$	2,911,692

Cash, cash equivalents and short-term investments consisted of the following as of December 3, 2010 (in thousands):



	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Current assets:
Cash	$	98,691	$	—	$	—		$	98,691
Cash equivalents:
Commercial paper	41,389		—		—			41,389
Money market mutual funds and repurchase agreements	477,259		—		—			477,259
Municipal securities	350		—		—			350
Time deposits	64,006		—		—			64,006
U.S. Treasury securities	68,195		1		—			68,196
Total cash equivalents	651,199		1		—			651,200
Total cash and cash equivalents	749,890		1		—			749,891
Short-term fixed income securities:
Corporate bonds and commercial paper	977,889		8,079		(1,450		)	984,518
Foreign government securities	33,079		309		(2		)	33,386
Municipal securities	119,608		29		(32		)	119,605
U.S. agency securities	229,772		778		(179		)	230,371
U.S. Treasury securities	336,441		2,828		(209		)	339,060
Subtotal	1,696,789		12,023		(1,872		)	1,706,940
Marketable equity securities	11,196		1,122		(1,134		)	11,184
Total short-term investments	1,707,985		13,145		(3,006		)	1,718,124
Total cash, cash equivalents and short-term investments	$	2,457,875	$	13,146	$	(3,006	)	$	2,468,015

See Note 4 for further information regarding the fair value of our financial instruments.

The following table summarizes the fair value and gross unrealized losses related to available-for-sale securities, aggregated by investment category, that have been in a continuous unrealized loss position for less than twelve months, as of December 2, 2011 and December 3, 2010 (in thousands):



	2011					2010
	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
Corporate bonds and commercial paper	$	408,178	$	(4,438	)	$	257,615	$	(1,450	)
Foreign government securities	—		—			4,531		(2		)
Marketable equity securities	—		—			9,380		(1,134		)
Municipal securities	17,125		(3		)	43,028		(32		)
U.S. Treasury and agency securities	133,857		(121		)	192,702		(388		)
Total	$	559,160	$	(4,562	)	$	507,256	$	(3,006	)

There were 213 securities and 168 securities in an unrealized loss position for less than twelve months at December 2, 2011 and at December 3, 2010, respectively.

The following table summarizes the fair value and gross unrealized losses related to available-for-sale securities, aggregated by investment category, that have been in a continuous unrealized loss position for more than twelve months, as of December 2, 2011 (in thousands):



	2011
	Fair Value		Gross Unrealized Losses
Corporate bonds and commercial paper	$	22,918	$	(232	)
Municipal securities	2,668		(1		)
Total	$	25,586	$	(233	)

As of December 2, 2011, there were 13 securities that were in an unrealized loss position for more than twelve months. As of December 3, 2010, there were no securities in a continuous unrealized loss position for more than twelve months.

The following table summarizes the cost and estimated fair value of short-term fixed income securities classified as short-term investments based on stated effective maturities as of December 2, 2011 (in thousands):



	Amortized Cost		Estimated Fair Value
Due within one year	$	646,632	$	646,694
Due between one and two years	619,557		620,778
Due between two and three years	427,913		429,660
Due after three years	210,802		212,793
Total	$	1,904,904	$	1,909,925

We review our debt and marketable equity securities classified as short-term investments on a regular basis to evaluate whether or not any security has experienced an other-than-temporary decline in fair value. We consider factors such as the length of time and extent to which the market value has been less than the cost, the financial condition and near-term prospects of the issuer and our intent to sell, or whether it is more likely than not we will be required to sell the investment before recovery of the investment's amortized cost basis. If we believe that an other-than-temporary decline exists in one of these securities, we write down these investments to fair value. For debt securities, the portion of the write-down related to credit loss would be recorded to interest and other income, net in our Consolidated Statements of Income. Any portion not related to credit loss would be recorded to accumulated other comprehensive income, which is reflected as a separate component of stockholders’ equity in our Consolidated Balance Sheets. For equity securities, the write-down would be recorded to investment gains (losses), net in our Consolidated Statements of Income. During fiscal 2011, we recorded $0.2 million in other-than-temporary impairment losses associated with our marketable equity securities and did not consider any of our debt securities to be other-than-temporarily impaired. During fiscal years 2010 and 2009, we did not consider any of our investments to be other-than-temporarily impaired.