Debt - Senior Credit Facility (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Disclosure Debt Additional Information [Abstract]
Loss on debt extinguishment and refinancing transactions	$ 6,996	$ 0	$ 20,554

Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment, as well as expenses incurred in connection with the refinancing of debt, primarily consisting of payments to third parties.

No definition available.

Name:	dnkn_LossOnDebtExtinguishmentAndRefinancingTransaction
Namespace Prefix:	dnkn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration