EARNINGS (LOSS) PER SHARE - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2023	Sep. 28, 2022	Sep. 27, 2023	Sep. 28, 2022
Numerator:
Net income (loss) attributable to Shake Shack Inc.—basic	$ 7,627	$ (2,024)	$ 13,041	$ (13,374)
Reallocation of net income attributable to non-controlling interests from the assumed conversion of Class B shares	509	(287)	696	(1,522)
Net income (loss) attributable to Shake Shack Inc.—diluted	$ 8,136	$ (2,024)	$ 13,737	$ (13,374)
Denominator:
Weighted-average shares of Class A common stock outstanding—basic (in shares)	39,460	39,274	39,402	39,221
Effect of dilutive securities:
Weighted-average shares of Class A common stock outstanding—diluted (in shares)	43,978	39,274	43,884	39,221
Earnings per share of Class A common stock—basic (in dollars per share)	$ 0.19	$ (0.05)	$ 0.33	$ (0.34)
Earnings per share of Class A common stock—diluted (in dollars per share)	$ 0.19	$ (0.05)	$ 0.31	$ (0.34)
Performance stock units
Effect of dilutive securities:
Incremental common shares (in shares)	11	0	11	0
Restricted stock units
Effect of dilutive securities:
Incremental common shares (in shares)	129	0	82	0
Convertible Notes
Effect of dilutive securities:
Incremental common shares (in shares)	1,467	0	1,467	0
Class B Common Stock
Numerator:
Reallocation of net income attributable to non-controlling interests from the assumed conversion of Class B shares	$ 509	$ 0	$ 696	$ 0
Effect of dilutive securities:
Incremental common shares (in shares)	2,837	0	2,845	0
Stock options
Effect of dilutive securities:
Incremental common shares (in shares)	74	0	77	0