Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Statement Of Financial Position [Abstract]
Allowances for receivables	$ 3,204	$ 2,915
Common Stock, par value	$ 1	$ 1
Common Stock, shares authorized	44,000,000	44,000,000
Common Stock, shares issued	10,199,521	10,171,664
Common Stock in treasury, shares	525,315	513,227