Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity Schedule of Dividends Declared (Details)

v2.4.0.6
Stockholders' Equity Schedule of Dividends Declared (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2011
Sep. 30, 2011
Jun. 30, 2011
Mar. 31, 2011
Dec. 31, 2010
Sep. 30, 2010
Jun. 30, 2010
Mar. 31, 2010
Dec. 31, 2009
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Dividends Payable [Line Items]                        
Common Stock, Dividends, Per Share, Declared $ 0.40 $ 0.40 $ 0.40 $ 0.40 $ 0.40 $ 0.39 $ 0.33 $ 0.36 $ 0.26 $ 1.60 $ 1.48 $ 0.26
Dividends Payable, Date Declared, Day, Month and Year Dec. 14, 2011 Sep. 14, 2011 Jun. 14, 2011 Mar. 02, 2011 Dec. 08, 2010 Sep. 13, 2010 Jun. 14, 2010 Mar. 12, 2010 Dec. 21, 2009      
Dividends Payable, Date of Record, Day, Month and Year Dec. 27, 2011 Sep. 26, 2011 Jun. 24, 2011 Mar. 14, 2011 Dec. 17, 2010 Sep. 30, 2010 Jun. 30, 2010 Mar. 31, 2010 Dec. 31, 2009      
Dividends Payable, Date to be Paid, Day, Month and Year Jan. 20, 2012 Oct. 20, 2011 Jul. 20, 2011 Apr. 14, 2011 Jan. 20, 2011 Oct. 21, 2010 Jul. 22, 2010 Apr. 23, 2010 Jan. 26, 2010      
Dividends Payable, Amount $ 56,239       $ 10,450         $ 56,239 $ 10,450