Policy Benefits And Losses Claims And Loss Expenses Payable (Present Value Expected Net Premiums) (Details) - USD ($) $ in Thousands		9 Months Ended
	Apr. 01, 2021	Dec. 31, 2023	Dec. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Liability For Future Policy Benefit Expected Net Premium [Roll Forward]
Balance, beginning of the year	$ 123,132
Effect of actual variances from expected variances						$ 2,580
Other	464,481
Effect of changes in discount rate assumptions (AOCI)						337,022
Life Insurance [Member]
Liability For Future Policy Benefit Expected Net Premium [Roll Forward]
Balance, beginning of the year		$ 419,687	$ 561,103
Beginning balance at original discount rate		437,525	496,048
Effect of actual variances from expected variances					$ 2
Adjust beginning of year balance				$ 427,376	496,046
Issuances		6,770	16,556
Interest accrual		14,439	16,673
Net premium collected		49,599	54,736
Ending balance at original discount rate		398,986	474,539
Effect of changes in discount rate assumptions (AOCI)		26,600	24,870
Balance, end of period		372,386	449,669
Life Insurance Segment [Member] | Oxford
Liability For Future Policy Benefit Expected Net Premium [Roll Forward]
Balance, beginning of the year		223,118	280,371
Beginning balance at original discount rate		225,071	242,741
Effect of actual variances from expected variances				1,621	1,259
Adjust beginning of year balance				224,487	241,482
Issuances		6,692	14,101
Interest accrual		8,367	9,036
Net premium collected		29,812	32,270
Ending balance at original discount rate		209,734	232,349
Effect of changes in discount rate assumptions (AOCI)		6,878	3,811
Balance, end of period		202,856	228,538
Health Insurance Product Line [Member]
Liability For Future Policy Benefit Expected Net Premium [Roll Forward]
Balance, beginning of the year	4,847
Effect of actual variances from expected variances						0
Other	$ 23,188
Effect of changes in discount rate assumptions (AOCI)						$ 18,341
Health Insurance Product Line [Member] | Oxford
Liability For Future Policy Benefit Expected Net Premium [Roll Forward]
Balance, beginning of the year		196,569	280,732
Beginning balance at original discount rate		212,454	253,307
Effect of actual variances from expected variances				8,650	1,257
Adjust beginning of year balance				$ 202,889	$ 254,564
Issuances		78	2,455
Interest accrual		6,072	7,637
Net premium collected		19,787	22,466
Ending balance at original discount rate		189,252	242,190
Effect of changes in discount rate assumptions (AOCI)		19,722	21,059
Balance, end of period		$ 169,530	$ 221,131