Description of Business	3 Months Ended
Mar. 24, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of BusinessDel Taco Restaurants, Inc. is a Delaware corporation headquartered in Lake Forest, California. The consolidated financial statements include the accounts of Del Taco Restaurants, Inc. and its wholly owned subsidiaries (collectively, the “Company” or “Del Taco”). The Company develops, franchises, owns, and operates Del Taco quick-service Mexican-American restaurants. At March 24, 2020, there were 296 company-operated and 300 franchise-operated Del Taco restaurants located in 15 states, including one franchise-operated unit in Guam. At March 26, 2019, there were 312 company-operated and 271 franchise-operated Del Taco restaurants located in 14 states, including one franchise-operated unit in Guam.

The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-URI http://asc.fasb.org/topic&trid=2122369

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-URI http://asc.fasb.org/topic&trid=2122149

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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