CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Accounts receivable, allowance	$ 2,578	$ 1,218
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	50,000	50,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	300,000	300,000
Common stock, shares issued	100,105	99,528
Common stock, shares outstanding	100,105	99,528