Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 28, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Accounts receivable, allowances	$ 866	$ 862
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	27,017,824	27,017,824
Treasury stock, shares	8,192,969	8,276,014
Stock trusts, shares	3,363,351	3,363,351