Reinsurance and Policy Benefits and Losses Claims and Loss Expenses Payable (Policy Benefits and Losses, Claims and Loss Expenses Payable for Property and Casualty Insurance) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Mar. 31, 2020
Reinsurance:
Unpaid losses and loss adjustment expense							$ 131,187
Total		$ 849,113		$ 880,202			$ 909,701	$ 1,040,951
Property and Casualty Insurance [Member]
Reinsurance:
Unpaid losses and loss adjustment expense	$ 131,192	131,192	$ 151,874	151,874	$ 159,162	$ 177,963
Reinsurance losses payable		1,287		1,133
Total		$ 132,479		$ 153,007