NON-CONTROLLING INTERESTS - Changes in Ownership Interests in SSE Holdings (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 23, 2020	Sep. 25, 2019	Sep. 23, 2020	Sep. 25, 2019
Noncontrolling Interest [Line Items]
Net income (loss) attributable to Shake Shack Inc.	$ (5,559)	$ 10,344	$ (22,730)	$ 21,920
Other comprehensive income:
Net change related to available-for-sale securities	0	0	1	0
Transfers (to) from non-controlling interests:
Total effect of changes in ownership interest on equity attributable to Shake Shack Inc.	(5,148)	32,985	113,854	50,971
Redemption or Exchange of Units
Transfers (to) from non-controlling interests:
Increase (decrease) in additional paid-in capital	44	1,634	239	7,115
Employee Stock Option
Transfers (to) from non-controlling interests:
Increase (decrease) in additional paid-in capital	367	1,789	627	2,718
Common Stock [Member] \| Class A Common Stock
Transfers (to) from non-controlling interests:
Increase (decrease) in additional paid-in capital	0	0	135,718	0
Additional Paid-In Capital \| Gramercy Tavern Merger
Transfers (to) from non-controlling interests:
Increase (decrease) in additional paid-in capital	$ 0	$ 19,218	$ 0	$ 19,218

This element represents the total net income attributable to the parent for the period and the effect of net changes during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not result in a deconsolidation of the subsidiary from the consolidated financial statements.

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