CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) (USD $)
3 Months Ended 9 Months Ended
Sep. 30, 2012
Jun. 30, 2012
Mar. 31, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Dividends on common stock, per share $ 0.0375 $ 0.0375 $ 0.0375 $ 0.0375 $ 0.1125 $ 0.1125