Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Allowance for doubtful patient accounts	$ 2,199,088	$ 1,891,334
Preferred stock, par value per share	$ 0.01	$ 0.01
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Common stock, par value per share	$ 0.01	$ 0.01
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	92,161,852	91,547,079
Common stock, shares outstanding	91,186,303	90,571,530
Treasury stock, shares	975,549	975,549