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Acquisition of Business - Narrative (Details) - Atlas Financial Holdings - Paratransit Business - USD ($) shares in Millions, $ in Millions | 12 Months Ended |
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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

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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. + Details
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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 Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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