Summary of Significant Accounting Policies (Insurance Reserves) (Details) - Workers' compensation and general liability [Member]	12 Months Ended
Dec. 29, 2019
Minimum [Member]
Insurance [Line Items]
Insurance, annual risk free rate, period	1 year
Maximum [Member]
Insurance [Line Items]
Insurance, annual risk free rate, period	5 years

The period of the annual risk free rate of monetary assets that have comparable maturities, used as the discount rate in calculating reserves for unresolved insurance claims and estimates of incurred but not reported claims.

No definition available.

Name:	blmn_InsuranceAnnualRiskFreeRatePeriod
Namespace Prefix:	blmn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration