ORGANIZATION AND RELATIONSHIPS - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 26, 2022 USD ($) location	Jun. 27, 2021 USD ($)	Jun. 26, 2022 USD ($) location franchise	Jun. 27, 2021 USD ($)	Dec. 26, 2021 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of franchise brands | franchise			17
Number of locations | location	2,354		2,354
Number of franchise units worldwide | franchise			2,261
Percent of total restaurants franchised	96.00%		96.00%
Income (loss) from operations	$ 13,203	$ 1,127	$ 13,689	$ 1,216
Accumulated deficit	(84,422)		(84,422)		$ (52,479)
Working capital	(163,400)		(163,400)
Redeemable preferred stock	135,000		135,000		67,500
Cash	$ 15,502		$ 15,502		$ 56,656