Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
Current assets:
Allowance for doubtful accounts	$ 8,756	$ 18,076
Shareholders' equity:
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, par value	$ 0.00	$ 0.00
Preferred stock, issued	0	0
Common stock, stated value	$ 1.00	$ 1.00
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	60,614,741	60,614,741
Treasury stock, shares	5,118,111	5,586,251