Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Change in amortization of accumulated actuarial losses, net of tax benefit	$ 0	$ 0	$ 2	$ 0
Change in fuel hedge mark-to-market, net of tax expense/(benefit)	$ (2)	$ (26)	$ (7)	$ (1)

The net tax benefit (expense) resulting from the adjustment out of other comprehensive income for prior service costs and actual losses recognized as a component of net period benefit cost during the period.

No definition available.

Name:	bni_ChangeInUnrecognizedPriorServiceCreditAndActuarialLossesTaxBenefitExpense
Namespace Prefix:	bni_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration