Income Taxes - Additional Information (Detail)	3 Months Ended
Nov. 21, 2012
Reconciliation of Unrecognized Tax Benefits [Line Items]
Period increase decrease of unrecognized tax benefits	1 year

Period Of Significant Increase Decrease In Unrecognized Tax Benefits

No definition available.

Name:	lub_PeriodOfSignificantIncreaseDecreaseInUnrecognizedTaxBenefits
Namespace Prefix:	lub_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration