Registration of securities issued in business combination transactions

Income Taxes (Details)

v2.4.0.8
Income Taxes (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 12 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Income Tax Disclosure [Line Items]          
Income tax expense $ (62) $ (82) $ (394) $ (342) $ (282)
Effective income tax rate 36.90% 37.10% 36.40% 35.80% 33.90%
United States Federal Statutory Tax Rate 35.00%   35.00% 35.00% 35.00%
Liberty
         
Income Tax Disclosure [Line Items]          
Current tax payments due to related parties $ 56   $ 70 $ 21