The price paid for a business acquisition as a percent of gross written premiums

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- Definition

The percent of ownership of an entity that is acquirable through a warrant or right

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Disposal Group Carrying Value of Assets and Liabilities as a Percentage of Total Assets and Liabilities

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- Definition

Estimated Proceeds From Divestiture Of Interest In Consolidated Subsidiaries

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- Definition

Gross written premiums eligible for renewal under the agreement

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Acquisitions and Sales of Businesses - Narrative (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2017	Jun. 30, 2020	Jun. 10, 2019
Business Acquisition [Line Items]
Income tax expense (benefit)	$ (30)	$ 34	$ (63)	$ 171
Neon Capital Limited
Business Acquisition [Line Items]
Estimated proceeds from divestiture of Neon	$ 6
Carrying value of assets and liabilities as a percentage of total assets and liabilities	1.00%		1.00%
Income tax expense (benefit)	$ (73)
Atlas Financial Holdings - Paratransit Business
Business Acquisition [Line Items]
Gross written premiums eligible for renewal					$ 110
Business acquisition, price as a percent of gross written premiums							15.00%
Warrant term to acquire shares							5 years
Number of shares able to be acquired with the warrant							2.4
Business acquisition, percentage of entity acquired by warrants							19.90%
Neon Capital Limited \| Neon Capital Limited Executives
Business Acquisition [Line Items]
Percentage of indirect noncontrolling interest acquired						100.00%
Equity securities \| Public company warrants \| Atlas Financial Holdings - Paratransit Business
Business Acquisition [Line Items]
Fair value of warrant on date received							$ 1