Accounts Receivable, Net (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Receivables [Abstract]
Allowance for bill adjustments and uncollectible accounts	$ 47	$ 39
Accounts receivable greater than 90 days old	$ 38	$ 31

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that have bill adjustments or are expected to be uncollectible.

No definition available.

Name:	bni_AllowanceForBillAdjustmentsAndDoubtfulAccountsReceivableCurrent
Namespace Prefix:	bni_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant