XML 27 R22.htm IDEA: XBRL DOCUMENT v2.4.0.6

Amortized Cost, Gross Unrealized Gains (Losses) and Fair Value of Available-For-Sale Securities (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2012	Jan. 31, 2012	Oct. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 240,083	$ 219,036	$ 178,261
Unrealized Gains	442	627	600
Unrealized (Losses)	(693)	(2,896)	(3,066)
Fair Value	239,832	216,767	175,795
Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	145,848	89,736	46,710
Unrealized Gains	230	156	27
Unrealized (Losses)	(13)	(38)	(88)
Fair Value	146,065	89,854	46,649
Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	94,235	129,300	131,551
Unrealized Gains	212	471	573
Unrealized (Losses)	(680)	(2,858)	(2,978)
Fair Value	93,767	126,913	129,146
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Fair Value	111,662	95,935	81,407
Corporate Bonds | Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	64,975	34,899	15,846
Unrealized Gains	89	7	1
Unrealized (Losses)	(7)	(28)	(67)
Fair Value	65,057	34,878	15,780
Corporate Bonds | Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	46,507	60,852	65,626
Unrealized Gains	155	277	261
Unrealized (Losses)	(57)	(72)	(260)
Fair Value	46,605	61,057	65,627
Municipal And Pre-Refunded Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Fair Value	51,505	60,234	64,462
Municipal And Pre-Refunded Municipal Bonds | Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	29,937	41,519	28,129
Unrealized Gains	98	135	25
Unrealized (Losses)	(6)	(10)	(21)
Fair Value	30,029	41,644	28,133
Municipal And Pre-Refunded Municipal Bonds | Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	21,456	18,410	36,041
Unrealized Gains	47	186	311
Unrealized (Losses)	(27)	(6)	(23)
Fair Value	21,476	18,590	36,329
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Fair Value	30,630	12,194	6,969
Certificates of Deposit | Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	28,676	5,225	735
Unrealized Gains	28
Fair Value	28,704	5,225	735
Certificates of Deposit | Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,925	6,970	6,234
Unrealized Gains	1		1
Unrealized (Losses)		(1)	(1)
Fair Value	1,926	6,969	6,234
US Treasury Bill Securities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	28,803	14,988
US Treasury Bill Securities | Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	10,582
Unrealized Gains	4
Fair Value	10,586
US Treasury Bill Securities | Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	18,211	14,982
Unrealized Gains	7	6
Unrealized (Losses)	(1)
Fair Value	18,217	14,988
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Fair Value	8,189	3,592
Commercial Paper | Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,178	3,580
Unrealized Gains	11	12
Fair Value	8,189	3,592
US Government Corporations and Agencies Securities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	4,713	9,627	2,001
US Government Corporations and Agencies Securities | Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,500	4,513	2,000
Unrealized Gains		2	1
Fair Value	3,500	4,515	2,001
US Government Corporations and Agencies Securities | Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,211	5,111
Unrealized Gains	2	2
Unrealized (Losses)		(1)
Fair Value	1,213	5,112
Auction Rate Securities
Schedule of Available-for-sale Securities [Line Items]
Fair Value	4,330	20,197	20,956
Auction Rate Securities | Long Term Investments
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,925	22,975	23,650
Unrealized (Losses)	(595)	(2,778)	(2,694)
Fair Value	$ 4,330	$ 20,197	$ 20,956

X

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 7

-Footnote 2

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13, 19

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_AvailableforsaleSecuritiesGrossUnrealizedGain
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

This item represents the gross unrealized losses for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLosses1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Details

Name:	us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration