DERIVATIVE CONTRACTS AND COLLATERALIZED INDEBTEDNESS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Derivative [Line Items]
Gain (loss) on derivative contracts, net	$ 219,114	$ (98,840)	$ 320,188	$ (152,405)
Change in the fair value of Comcast common stock included in gain (loss) on investments	(325,601)	125,019	(476,374)	198,472
Gain (loss) on interest rate swap contracts, net	39,868	(21,574)	163,015	54,079
Comcast stock
Derivative [Line Items]
Change in the fair value of Comcast common stock included in gain (loss) on investments	(325,601)	125,000	(476,374)	198,453
Notes related to derivative contracts
Derivative [Line Items]
Gain (loss) on derivative contracts, net	$ 219,114	$ (98,840)	$ 320,188	$ (152,405)

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