NON-CONTROLLING INTERESTS - Ownership Interest in SSE Holdings (Details) - shares	Jun. 24, 2020	Dec. 25, 2019
Noncontrolling Interest [Line Items]
Number of LLC Interests held by Shake Shack Inc. (in shares)	38,236,538	34,417,302
Number of LLC Interests held by non-controlling interest holders (in shares)	3,117,002	3,145,197
Total LLC Interests outstanding (in shares)	41,353,540	37,562,499
Total LLC Interests outstanding (as a percentage)	100.00%	100.00%
Shake Shack Inc.
Noncontrolling Interest [Line Items]
Number of LLC Interests held by Shake Shack Inc. (as a percentage)	92.50%	91.60%
Non-Controlling Interest Holders
Noncontrolling Interest [Line Items]
Number of LLC Interests held by non-controlling interest holders (as a percentage)	7.50%	8.40%