CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets
Allowance for doubtful accounts receivable	$ 20,364	$ 20,392
Stockholders' Equity
Preferred stock, par value per share	$ 100	$ 100
Preferred stock, shares authorized	100,000	100,000
Preferred stock, shares issued	0	0
Common stock, par value per share	$ 1.0	$ 1.0
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	255,320,345	254,119,478