CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current assets:
Allowances for doubtful accounts receivable	$ 24,987	$ 29,856
Stockholders' Equity:
Preferred stock, par value (in dollars per share)	$ 100	$ 100
Preferred stock, issued (in shares)	0	0
Preferred stock, authorized (in shares)	100,000	100,000
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, authorized (in shares)	500,000,000	500,000,000
Common stock, issued (in shares)	250,591,610	249,361,340