NON-CONTROLLING INTERESTS NON-CONTROLLING INTERESTS - Redemption of LLC Interests (Details) - shares	3 Months Ended	6 Months Ended
Jun. 24, 2020	Jun. 26, 2019	Jun. 24, 2020	Jun. 26, 2019
Limited Liability Company
Class of Stock [Line Items]
Number of units redeemed (in shares)	0	722,306	28,195	826,138
Redemptions by NCI Holders \| Limited Liability Company
Class of Stock [Line Items]
Number of units redeemed (in shares)	0	722,306	28,195	826,138
Common Stock [Member] \| Class A Common Stock
Class of Stock [Line Items]
Shares of Class A common stock issued in connection with redemptions of LLC Interests	0	722,306	28,195	826,138
Common Stock [Member] \| Class B Common Stock
Class of Stock [Line Items]
Shares of Class A common stock issued in connection with redemptions of LLC Interests		(722,306)	(28,195)	(826,138)
Shares of Class B common stock surrendered and canceled	0	722,306	28,195	826,138

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The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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