Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) (USD $) In Millions, unless otherwise specified	11 Months Ended	12 Months Ended	1 Months Ended
Dec. 31, 2010 Successor [Member]	Dec. 31, 2012 Successor [Member]	Dec. 31, 2011 Successor [Member]	Feb. 12, 2010 Predecessor [Member]
Change in amortization of accumulated actuarial losses, net of tax (benefit)/expense	$ (8)	$ (16)	$ (125)	$ 1
Change in fuel hedge mark-to-market, net of tax expense/(benefit)	$ 26	$ (7)	$ (18)	$ (28)

The net tax (benefit) expense resulting from the change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect.

No definition available.

Name:	bni_FuelInterestHedgeMarkToMarketTaxBenefitExpense
Namespace Prefix:	bni_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration