Fair Value of Financial Instruments - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 01, 2022 shares	Oct. 31, 2021 USD ($) tranche
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Class of warrant or right, exercisable | shares			2,400,000
Root, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, not readily determinable fair value				$ 126
Root, Inc. | Warrant
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, number of tranches | tranche				8
Level 3 | Root, Inc. | Warrant
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities, fair value	$ 30
Deferred revenue	30
Warrants to acquire Root's Class A common stock	75
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Purchase price adjustment receivable	37	$ 34
Purchase price adjustment receivable, fair value adjustment	(14)	20
Fair Value, Measurements, Recurring | Level 3 | Variable Interest Entity, Not Primary Beneficiary
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Sales of beneficial interests	43	1
Proceeds from sale of beneficial interests	$ 43	$ 1
Fair Value, Measurements, Recurring | Minimum | Level 3 | Variable Interest Entity, Not Primary Beneficiary | Measurement Input, Discount Rate | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input, discount rate	0.071	0.011
Fair Value, Measurements, Recurring | Maximum | Level 3 | Variable Interest Entity, Not Primary Beneficiary | Measurement Input, Discount Rate | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Measurement input, discount rate	0.113	0.100