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Carrying amount of liabilities as of the balance sheet date pertaining to amounts received by the insurer or reinsurer from the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Increase (Decrease) In Earned Unbilled Audit Premiums

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Summary of Significant Accounting Policies (Details) $ in Millions		3 Months Ended	12 Months Ended
	Apr. 02, 2019	Dec. 31, 2019 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) shares
Accounting Policies [Abstract]
Conversion ratio	0.6667
Unbilled Audit Premiums		$ 4	$ 4	$ (4)	$ 8
Indefinite-lived Intangible Assets [Line Items]
Basic weighted average number of shares outstanding (in shares) \| shares			190,722	190,048	187,265
Deposit contracts, liabilities		41	$ 41	$ 45
Depreciation			54	54	$ 50
Interest payments			160	155	145
Income taxes paid			125	186	$ 207
Other Assets
Indefinite-lived Intangible Assets [Line Items]
Intangible assets, net (excluding goodwill)		$ 99	$ 99	$ 104
Grantor Trust \| Restricted Stock Units (RSUs)
Indefinite-lived Intangible Assets [Line Items]
Basic weighted average number of shares outstanding (in shares) \| shares		7,575,168