Employment Benefit Plans Expected Benefit Payments (Details) (Successor [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected benefit payments, 2013	$ 162	[1]
Expected benefit payments, 2014	156	[1]
Expected benefit payments, 2015	157	[1]
Expected benefit payments, 2016	157	[1]
Expected benefit payments, 2017	155	[1]
Expected benefit payments, 2018 - 2022	736	[1]
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected benefit payments, 2013	25
Expected benefit payments, 2014	24
Expected benefit payments, 2015	24
Expected benefit payments, 2016	23
Expected benefit payments, 2017	22
Expected benefit payments, 2018 - 2022	$ 101

[1] Primarily consists of the BNSF Retirement Plan payments, which are made from the plan trust and do not represent an immediate cash outflow to the Company.