DERIVATIVE CONTRACTS AND COLLATERALIZED INDEBTEDNESS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Derivative [Line Items]
Gain (Loss) on Price Risk Derivative Instruments Not Designated as Hedging Instruments	$ 101,074	$ (53,565)
Change in the fair value of Comcast common stock included in gain (loss) on investments	(150,773)	73,453
Gain (Loss) on Interest Rate Derivative Instruments Not Designated as Hedging Instruments	123,147	75,653
Notes related to derivative contracts
Derivative [Line Items]
Gain (Loss) on Price Risk Derivative Instruments Not Designated as Hedging Instruments	$ 101,074	$ (53,565)

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