CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY      
Reclassification of unrealized gain (loss) on interest rate swaps, benefit (expense)   $ 903 $ (276)
Unrealized loss on derivatives, tax expense $ 31