Selected Quarterly Financial and Earnings Data (Unaudited) (Details) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jul. 01, 2018 USD ($)	Apr. 01, 2018 USD ($)	Dec. 31, 2017 USD ($)	Oct. 01, 2017 USD ($)	Jul. 02, 2017 USD ($)	Apr. 02, 2017 USD ($)	Dec. 30, 2018 USD ($) restaurant	Dec. 31, 2017 USD ($)	Jan. 01, 2017 USD ($)	Dec. 30, 2012
Quarterly Financial Information Disclosure [Abstract]
Restaurants Acquired	10			1			17		44		4	278
Acquisition-related costs	$ 400	$ 800	$ 100	$ 100	$ 100	$ 500	$ 500	$ 700
Impairment and other lease charges	$ 300	$ 200	$ 2,900	$ 300	$ 800	$ 1,000	$ 400	$ 500	$ 3,685	$ 2,827	$ 2,355
Number of Restaurants	849	838	807	807	807	798	799	788	849	807
Litigation Settlement, Expense											$ 1,850

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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- Definition

Represents the number of restaurants.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Amount of restructuring charges, remediation cost, and asset impairment loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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