NON-CONTROLLING INTERESTS - Changes in Ownership Interests in SSE Holdings (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 24, 2020	Jun. 26, 2019	Jun. 24, 2020	Jun. 26, 2019
Noncontrolling Interest [Line Items]
Net income (loss) attributable to Shake Shack Inc.	$ (16,211)	$ 9,030	$ (17,171)	$ 11,576
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.	119,343	13,873	119,002	17,988
Redemption or Exchange of Units
Transfers (to) from non-controlling interests:
Increase (decrease) in additional paid-in capital	0	4,886	195	5,480
Employee Stock Option
Transfers (to) from non-controlling interests:
Increase (decrease) in additional paid-in capital	(164)	(43)	260	932
Common Stock [Member] \| Class A Common Stock
Transfers (to) from non-controlling interests:
Increase (decrease) in additional paid-in capital	$ 135,718	$ 0	$ 135,718	$ 0

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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