CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Fixed maturities available-for-sale, amortized cost	$ 722.2	$ 696.8
Short -term investments, cost	143.1	110.4
Premium receivable, allowance for doubtful accounts	$ 2.7	$ 1.6
Common stock, par value (usd per share)	$ 0.00001	$ 0.00001
Common stock, authorized (in shares)	200,000,000	200,000,000
Common stock, issued (in shares)	69,120,346	61,660,996
Common stock, outstanding (in shares)	69,120,346	61,660,996

Short Term Investments, Cost

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.

+ References

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- References

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