v3.20.1
Equity Method Investments - Narrative (Details)
1 Months Ended 3 Months Ended 12 Months Ended
Mar. 31, 2020
USD ($)
subsidiary
Mar. 31, 2018
USD ($)
Mar. 31, 2020
USD ($)
Mar. 31, 2019
USD ($)
Mar. 31, 2018
Dec. 31, 2019
USD ($)
Schedule of Equity Method Investments [Line Items]            
Return of capital from equity method investee     $ 91,000,000 $ 0    
Equity method investments $ 1,299,000,000   $ 1,299,000,000     $ 1,364,000,000
Depreciation of the Ruble against the U.S. dollar     22.00%      
MLU B.V.            
Schedule of Equity Method Investments [Line Items]            
Equity ownership interest 38.00% 38.00% 38.00%   38.00%  
Contingent ownership percentage         35.00%  
Weighted average remaining useful life     4 years 7 months 6 days      
Impairment of equity method investments     $ 0      
Equity method investments $ 1,244,000,000   1,244,000,000     1,224,000,000
Event Center Office Partners, LLC            
Schedule of Equity Method Investments [Line Items]            
Impairment of equity method investments     $ 0     $ 0
Ownership interest     45.00%      
Equity method investments $ 50,000,000   $ 50,000,000      
Variable Interest Entity, Not Primary Beneficiary | Event Center Office Partners, LLC            
Schedule of Equity Method Investments [Line Items]            
Payments to acquire variable interest entity   $ 136,000,000        
Ownership interest   45.00%       45.00%
LLC Partner One | Variable Interest Entity, Not Primary Beneficiary | Event Center Office Partners, LLC            
Schedule of Equity Method Investments [Line Items]            
Ownership interest   45.00%        
LLC Partner Two | Variable Interest Entity, Not Primary Beneficiary | Event Center Office Partners, LLC            
Schedule of Equity Method Investments [Line Items]            
Ownership interest   10.00%        
Event Center Office Partners, LLC            
Schedule of Equity Method Investments [Line Items]            
Number of wholly owned subsidiaries | subsidiary 2