CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Sep. 26, 2014	Dec. 31, 2013
Statement Of Financial Position [Abstract]
Accounts receivable, allowance	$ 435	$ 575
Common shares, no par value	$ 0	$ 0
Common shares, Issued	34,209	33,991
Common shares, outstanding	34,209	33,991