v2.4.0.6

Fair Value Measurements

9 Months Ended

Oct. 31, 2012

Fair Value Measurements [Abstract]

Fair Value Measurements

Note 5. Fair Value Measurements

        We measure our financial assets and liabilities at fair value at the end of each reporting period using a fair value hierarchy that requires that we maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s classification within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. Three levels of inputs may be used to measure fair value:

Level 1 – Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets.

Level 2 – Include other inputs that are directly or indirectly observable in the marketplace.

Level 3 – Unobservable inputs that are supported by little or no market activity.

We have no financial assets or liabilities measured using Level 3 inputs. The following tables present information about our assets that are measured at fair value on a recurring basis using the above input categories (in thousands):

		Fair Value Measurements at October 31, 2012
Description		Level 1				Level 2				Total
U.S. agency obligations		$	—			$	608,675			$	608,675
U.S. treasury securities			70,146				—				70,146
Commercial paper			—				42,697				42,697
Certificates of deposit			—				250				250
U.S. corporate securities			—				12,027				12,027
Municipal securities			—				1,360				1,360
Money market funds			51,047				—				51,047
		$	121,193			$	665,009			$	786,202
Included in cash and cash equivalents										$	431,805
Included in marketable securities										$	354,397
		Fair Value Measurements at January 31, 2012
Description		Level 1				Level 2				Total
U.S. agency obligations		$	—			$	14,316			$	14,316
Commercial paper			—				23,785				23,785
U.S. corporate securities			—				20,380				20,380
Municipal securities			—				15,125				15,125
Money market funds			27,152				—				27,152
		$	27,152			$	73,606			$	100,758
Included in cash and cash equivalents										$	47,124
Included in marketable securities										$	53,634

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- Definition

The entire disclosure of the fair value measurement of assets and liabilities, which includes financial instruments measured at fair value that are classified in shareholders' equity, which may be measured on a recurring or nonrecurring basis.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19279-110258



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19190-110258



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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 33

-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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-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 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 10

-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 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 6

-Footnote 4

-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.

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