Investments - Investments with Related Party (Details) - Cannae - Common Stock - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Included in equity securities shares of related party (in shares)	5,706,134	5,706,134
Fair value of shares owned of related party	$ 191	$ 212

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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