Goodwill and other intangible assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Goodwill [Roll Forward]
Goodwill	$ 1,182,786	$ 1,182,750	$ 1,184,066
Accumulated impairment charges	(294,478)	(294,478)	(294,478)
Goodwill disposed		(1,331)
Goodwill, Translation and Purchase Accounting Adjustments	36	15
Net Balance	888,308	888,272	889,588
Dunkin’ Donuts U.S.
Goodwill [Roll Forward]
Goodwill	1,148,579	1,148,579	1,149,910
Accumulated impairment charges	(270,441)	(270,441)	(270,441)
Goodwill disposed		(1,331)
Effects of foreign currency adjustments	0	0
Goodwill, Translation and Purchase Accounting Adjustments	0	0
Net Balance	878,138	878,138	879,469
Dunkin’ Donuts International
Goodwill [Roll Forward]
Goodwill	10,170	10,134	10,119
Accumulated impairment charges	0	0	0
Goodwill disposed		0
Effects of foreign currency adjustments	36	15
Goodwill, Translation and Purchase Accounting Adjustments	36	15
Net Balance	10,170	10,134	10,119
Baskin-Robbins International
Goodwill [Roll Forward]
Goodwill	24,037	24,037	24,037
Accumulated impairment charges	(24,037)	(24,037)	(24,037)
Goodwill disposed		0
Effects of foreign currency adjustments	0	0
Net Balance	$ 0	$ 0	$ 0

Goodwill, disposed or held for sale

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

+ Details

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- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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