Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
Current assets:
Accounts receivable, less allowances	$ 12,083	$ 10,811
Property, plant and equipment:
Accumulated amortization of intangibles	$ 25,086	$ 24,455
Equity:
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 1.00	$ 1.00
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	87,850,292	87,850,292
Treasury stock, shares	25,592,543	26,205,336