Acquisition of Business - Narrative (Details) - Atlas Financial Holdings - Paratransit Business - USD ($) shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2017	Jun. 10, 2019
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%
Equity securities \| Public company warrants
Business Acquisition [Line Items]
Fair value of warrant on date received		$ 1

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

+ References

No definition available.

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- Definition

Gross written premiums eligible for renewal under the agreement

+ References

No definition available.

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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.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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