Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	3 Months Ended
Apr. 30, 2011	May 01, 2010
Cash flows from operating activities:
Net income	$ 17,810	$ 15,808
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	6,246	5,856
Loss on disposals of property, plant and equipment	61	23
Non-cash equity compensation	558	0
Increase (decrease) in deferred taxes	418	(813)
Net (increase) in operating working capital and other components	(37,978)	(22,147)
Net cash (used in) operating activities	(12,885)	(1,273)
Cash flows from investing activities:
Capital expenditures	(5,592)	(3,978)
Proceeds from maturities of short-term investments	179,814	64,922
Payments to acquire short-term investments	(158,979)	(34,875)
Net cash provided by investing activities	15,243	26,069
Cash flows from financing activities:
Income tax benefit from exercise of stock options	61	0
Net proceeds from exercise of stock options	67	0
Net cash provided by financing activities	128	0
Net increase in cash and cash equivalents	2,486	24,796
Cash and cash equivalents - beginning of period	80,979	21,853
Cash and cash equivalents - end of period	$ 83,465	$ 46,649

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7, 26

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 8, 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7
-Footnote 1

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 1
-Article 5