Investments (Narratives) (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2023
Insurance Regulatory Authorites:
Assets held by insurance regulators	$ 21.2		$ 23.4
Available for sale securities:
Fair value of sold available for sale securites	165.4	$ 105.5
Available for sale securities, realized gains	1.5	0.8
Available for sale securities, gross realized losses	1.1	$ 0.3
Other-than-temporary impairments	$ 225.0

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

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