Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Operating Loss Carryforwards [Line Items]
Valuation allowance, amount	$ 85.3
US Treasury Securities
Operating Loss Carryforwards [Line Items]
Debt securities	354.1	$ 354.1
Internal Revenue Service (IRS)
Operating Loss Carryforwards [Line Items]
Current federal income tax liability	$ 19.9	$ 19.9

Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes.

+ References

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