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Significant Transactions (Universal Beijing Resort) (Details) $ in Millions, ¥ in Billions	Jun. 30, 2018 USD ($)	Jun. 30, 2018 CNY (¥)
Universal Beijing Resort [Member]
Variable Interest Entity [Line Items]
Ownership percentage in variable interest entity	30.00%	30.00%
Maximum borrowing capacity of variable interest entity	$ 4,000	¥ 26.6
Consolidated variable interest entity's assets included in condensed consolidated balance sheet	1,200
Consolidated variable interest entity's liabilities included in condensed consolidated balance sheet	$ 587
NBCUniversal Media LLC [Member] | Universal Beijing Resort [Member]
Variable Interest Entity [Line Items]
Ownership percentage in variable interest entity	30.00%	30.00%
Maximum borrowing capacity of variable interest entity	$ 4,000	¥ 26.6
Consolidated variable interest entity's assets included in condensed consolidated balance sheet	1,200
Consolidated variable interest entity's liabilities included in condensed consolidated balance sheet	587
Universal Beijing Resort Term Loans [Member]
Variable Interest Entity [Line Items]
Debt face amount	235
Universal Beijing Resort Term Loans [Member] | NBCUniversal Media LLC [Member]
Variable Interest Entity [Line Items]
Debt face amount	$ 235

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