Investments (Narratives) (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2023	Mar. 31, 2023
Real Estate [Abstract]
Allowance for probable losses and any unamortized premiums or discount	$ 0.5
Insurance Regulatory Authorites:
Assets held by insurance regulators	21.4	$ 23.4
Available for sale securities:
Fair value of sold available for sale securites	113.0
Other-than-temporary impairments	$ 225.0

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 825
-Section 50
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=123600598&loc=SL75763979-209797

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Amount, before tax, of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in other comprehensive income (OCI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (g)
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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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