Consolidated Statements of Shareholders' Equity - Successor - USD ($)	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings (Accumulated Deficit)
Beginning Balance at Dec. 29, 2015	$ 368,377,000	$ 4,000	$ 372,260,000	$ 0	$ (3,887,000)
Beginning Balance, Shares at Dec. 29, 2015		38,802,425
Net income (loss)	20,913,000				20,913,000
Stock-based compensation	4,096,000	$ 0	4,096,000
Common stock of Del Taco Restaurants, Inc. released from possible redemption, Shares		0
Other comprehensive income (loss), net of tax	172,000			172,000
Comprehensive income (loss)	21,085,000
Stock-based compensation	5,000		5,000
Tax withholdings on restricted stock vesting	(916,000)		(916,000)
Restricted stock awards vested, shares		164,336
Exercise of stock options, shares		500
Issuance of common stock (in shares)		1,533,542
Issuance of common stock in exchange for warrants	0	$ 0	0
Repurchase of common stock, shares		(1,347,300)
Repurchase of common stock, value	(15,314,000)		(15,314,000)
Ending Balance at Jan. 03, 2017	377,333,000	$ 4,000	360,131,000	172,000	17,026,000
Ending Balance, Shares at Jan. 03, 2017		39,153,503
Net income (loss)	49,871,000				49,871,000
Other comprehensive income (loss), net of tax	(158,000)			(158,000)
Comprehensive income (loss)	49,713,000
Stock-based compensation	4,876,000		4,876,000
Tax withholdings on restricted stock vesting	(1,923,000)		(1,923,000)
Restricted stock awards vested, shares		257,518
Restricted stock awards vested, value		$ 0
Exercise of stock options, shares		9,750
Exercise of stock options, value	99,000		99,000
Repurchase of common stock, shares		(986,497)
Stock Repurchased During Period, Value		$ 0
Repurchase of common stock, value	(13,849,000)		(13,849,000)
Ending Balance at Jan. 02, 2018	416,249,000	$ 4,000	349,334,000	14,000	66,897,000
Ending Balance, Shares at Jan. 02, 2018		38,434,274
Adjustment for adoption of new revenue recognition standard, net of tax	(707,000)				(707,000)
Net income (loss)	18,959,000				18,959,000
Other comprehensive income (loss), net of tax	166,000			166,000
Comprehensive income (loss)	19,125,000
Stock-based compensation	6,079,000		6,079,000
Tax withholdings on restricted stock vesting	(2,378,000)		(2,378,000)
Restricted stock awards vested, shares		257,389
Restricted stock awards vested, value		$ 0
Exercise of stock options, shares		21,750
Exercise of stock options, value	222,000		222,000
Repurchase of common stock, shares		(1,408,071)
Stock Repurchased During Period, Value		$ 0
Repurchase of common stock, value	(16,316,000)		(16,316,000)
Ending Balance at Jan. 01, 2019	$ 422,274,000	$ 4,000	$ 336,941,000	$ 180,000	$ 85,149,000
Ending Balance, Shares at Jan. 01, 2019		37,305,342