XML 36 R35.htm IDEA: XBRL DOCUMENT v2.4.0.6
Earnings per Share Weighted Average Dilutive Shares and Offerings (Details) (USD $)
3 Months Ended
Mar. 31, 2013
Sep. 30, 2012
Sep. 19, 2012
Schedule of Stock Offering [Line Items]      
Weighted average share impact from the conversion of Series A-1 Preferred Stock 3,058,607    
Tangible Equity Units [Member]
     
Schedule of Stock Offering [Line Items]      
Weighted average share impact resulting from offerings 2,841,650    
Stock Issued During Period, Shares, New Issues   2,300,000  
Shares issued as a result of the underwriter's exercise of their over-allotment option   300,000  
Stated par value per share     $ 100
Class A common shares [Member]
     
Schedule of Stock Offering [Line Items]      
Weighted average share impact resulting from offerings 3,791,004    
Stock Issued During Period, Shares, New Issues   3,791,004  
Sale of stock, price per share     $ 64.75
Shares issued as a result of the underwriter's exercise of their over-allotment option   525,000