Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 29, 2013	Dec. 31, 2012
Current assets
Accounts receivable allowance for doubtful accounts	$ 586	$ 541
Stockholders' equity:
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value per share	$ 0.001	$ 0.001
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	63,238,000	62,908,000
Common stock, shares outstanding	59,057,000	58,727,000
Treasury stock, shares	4,181,000	4,181,000