Nature of Business and Basis of Presentation - Additional Information (Details) - USD ($) $ in Millions		9 Months Ended	12 Months Ended
	Feb. 01, 2019	Sep. 30, 2020	Dec. 31, 2019	Jun. 30, 2020	Jan. 01, 2020	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounting standards update		us-gaap:AccountingStandardsUpdate201613Member	us-gaap:AccountingStandardsUpdate201613Member
Total stockholders’ equity		$ 2,341	$ 2,231	$ 2,145		$ 1,767	$ 1,678	$ 1,945
Pacific union
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash consideration	$ 116
Cumulative effect, period of adoption, adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total stockholders’ equity			7
Cumulative effect, period of adoption, adjustment | Advances and other receivables reserve
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses					$ 7
Cumulative effect, period of adoption, adjustment | Other assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses					2
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total stockholders’ equity		$ 1,243	1,122	$ 1,034		$ 659	$ 575	$ 848
Retained Earnings | Cumulative effect, period of adoption, adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total stockholders’ equity			$ 7		9
Retained Earnings | Cumulative effect, period of adoption, adjustment after tax
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total stockholders’ equity					$ 7