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FAIR VALUE MEASUREMENTS - Additional Information (Details) $ in Millions		6 Months Ended
	Nov. 07, 2022	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2020 USD ($)	Oct. 02, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other liabilities at fair value		$ 220	$ 560
Redeemable noncontrolling interest, cost of debt		10.20%
Redeemable noncontrolling interest, exit revenue multiple		1.3
Redeemable noncontrolling interest, weighted average cost of capital		17.50%
Redeemable noncontrolling interest, revenue multiple		1.4
Redeemable noncontrolling interest, control premium		10.00%
Median
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Redeemable noncontrolling interest, beta		1.05
Redeemable noncontrolling interest, equity to debt, ratio		1.6315789
Arithmetic Average
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Redeemable noncontrolling interest, beta		1.04
Redeemable noncontrolling interest, equity to debt, ratio		1.8571428
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other liabilities at fair value		$ 220	$ 560
Fox Options \| Discount Rate \| Valuation Technique, Discounted Cash Flow
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights measurement input		0.165	0.180
Fox Options \| Discount For Lack Of Marketability And Control
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights measurement input		0.300	0.300
Fox Options \| Discount for Lack of Marketability \| Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights measurement input		0.139	0.139
Fox Options \| Discount for Lack of Marketability \| Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights measurement input		0.222	0.222
Fox Options \| Discount For Lack Of Control Based On Fan Duels Equity Ownership And Data Based On Megarstat Studies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights measurement input		0.200	0.200
Fox Options \| Price Volatility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights measurement input		0.400	0.320
Fox Options \| Probabiltiy Of Market Participant Submitting And Obtaining License
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights measurement input		0.750	0.750
Fox Options \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other liabilities at fair value		$ 220	$ 560
Fox Corporation \| Fox Options
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants and rights outstanding		4,900	4,800	$ 3,700
Warrants and rights outstanding, annual escalator percentage of option price	5.00%
Warrants and rights outstanding, term				10 years
FanDuel Group Parent LLC \| FSG Services, LLC
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Option to acquire ownership percentage					18.60%
FanDuel Group Parent LLC \| Flutter Entertainment plc
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Subsidiary, ownership percentage, parent				37.20%
USD Senior Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value		2,152	2,190
Euro Senior Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value		1,539	1,603
GBP Senior Secured Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value		$ 928	$ 952