Condensed Consolidated Statements of Cash Flows (USD $) In Thousands	6 Months Ended
	Jul. 30, 2011		Jul. 31, 2010
Cash flows from operating activities:
Net income	$ 38,364		$ 32,287
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	12,595		11,802
Loss on disposals of property, plant and equipment	122		91
Non-cash equity compensation	1,369		234
Increase (decrease) in deferred taxes	1,151		(1,358)
Net (increase) in operating working capital and other components	(43,093)		(17,988)
Net cash provided by operating activities	10,508		25,068
Cash flows from investing activities:
Capital expenditures	(14,039)	[1]	(12,471)	[1]
Proceeds from maturities of short-term investments	189,789		99,895
Payments to acquire short-term investments	(176,975)		(44,850)
Net cash provided by (used in) investing activities	(1,225)		42,574
Cash flows from financing activities:
Income tax benefit from exercise of stock options	1,883		0
Net proceeds from exercise of stock options	546		0
Net cash provided by financing activities	2,429		0
Net increase in cash and cash equivalents	11,712		67,642
Cash and cash equivalents - beginning of period	80,979		21,853
Cash and cash equivalents - end of period	$ 92,691		$ 89,495

[1] Capital expenditures include payments for property, plant and equipment made for the reportable segment.