Annual report pursuant to Section 13 and 15(d)

Related Party Transactions (Details)

v2.4.0.6
Related Party Transactions (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Related Party Transactions (Textual) [Abstract]      
Related party transactions $ 0 $ 0 $ 0
Amount included in accounts payable and accrued liabilities $ 0 $ 0