Related Party Transactions - Summary of Amounts Included in Condensed Consolidated Statements of Operations Related to Fee for Service Arrangement (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Equity in earnings from unconsolidated affiliates	$ 3	$ 1
BRE Ace LLC
Related Party Transaction [Line Items]
Equity in earnings from unconsolidated affiliates	3	1
Commissions and other fees	$ 23	$ 36

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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