Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Feb. 02, 2013	Jan. 28, 2012	Jan. 29, 2011
Cash flows from operating activities
Net income (loss)	$ (101,768)	$ (168,045)	$ 9,147
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	23,870	28,952	27,680
Stock-based compensation	10,595	12,025	12,577
Provision for excess and obsolete inventory	7,053	8,955	488
Provision for (recovery of) sales returns, discounts and doubtful accounts	(158)	54	260
Deferred income taxes	12,398	(10,221)	(4,806)
(Gain) loss on disposal of software, equipment and leasehold improvements	(437)	173	449
Impairment of investment			5,203
Gain on acquisition	(1,389)
Non-cash restructuring costs	2,111
Tax effect related to stock options	(345)	1,595	2,320
Excess tax (benefit) expense from stock-based compensation	345	(1,938)	(2,320)
Accretion of contributed leasehold improvements	(206)	(260)	(176)
Impairment of goodwill, intangible assets, IP, mask sets and design tools	11,174	111,278
Changes in operating assets and liabilities:
Accounts receivable	13,100	10,114	4,517
Inventory	3,699	6,964	(20,015)
Prepaid expenses and other current assets	1,268	(443)	(697)
Other non-current assets	(3,954)	156	84
Accounts payable	4,473	(7,968)	4,705
Accrued liabilities, compensation and related benefits	1,391	(4,114)	1,028
Income taxes payable and other long-term liabilities	2,135	577	1,428
Net cash provided by (used in) operating activities	(14,645)	(12,146)	41,872
Cash flows from investing activities
Restricted cash		(153)	(116)
Purchases of marketable securities	(21,354)	(88,072)	(130,530)
Sales and maturities of marketable securities	94,043	88,515	90,320
Purchases of software, equipment, leasehold improvements and IP	(17,629)	(14,239)	(14,653)
Net cash paid in connection with acquisitions	(38,210)	(5,000)
Purchases of long-term investments		(2,142)	(2,300)
Repayment of note receivable	250	150
Purchase of notes receivable		(2,500)	(1,150)
Net cash provided by (used in) investing activities	17,100	(23,441)	(58,429)
Cash flows from financing activities
Net proceeds from exercise of employee stock options and stock purchase rights	4,574	5,377	5,243
Excess tax benefit (expense) from stock-based compensation	(345)	1,938	2,320
Net cash provided by financing activities	4,229	7,315	7,563
Effect of foreign exchange rate changes on cash and cash equivalents	251	(177)	(221)
Net increase (decrease) in cash and cash equivalents	6,935	(28,449)	(9,215)
Cash and cash equivalents, beginning of period	44,283	72,732	81,947
Cash and cash equivalents, end of period	51,218	44,283	72,732
Supplemental disclosure of cash flow information
Cash paid for interest			148
Cash paid for income taxes	$ 2,673	$ 1,330	$ 1,623