Treasury Stock (Details) (USD $)	3 Months Ended
	Mar. 30, 2013	Feb. 19, 2013
Treasury Stock
Maximum number of shares authorized to be repurchased		4,000,000
Shares of common stock repurchased	6,800
Amount at which shares of common stock were repurchased	$ 272,000
Shares of common stock withheld and repurchased to satisfy the statutory withholding tax liability for certain foreign employees	5,600
Amount at which shares of common stock were withheld and repurchased to satisfy the statutory withholding tax liability for certain foreign employees	$ 204,000