Fair Value Measurements (Financial instruments level within the fair value hierarchy) (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024
Assets:
Fixed maturities - available for sale	$ 2,395,890	$ 2,442,504
Preferred stock	22,067	21,260
Common stock	51,999	45,014
Derivatives	17,190	18,930
Total	2,319,178	2,527,708
Liabilities:
Guaranteed residual values of TRAC leases	9,880	9,300
Liabilities from investment contracts	2,295,851	2,290,096
Market risk benefits	13,447	13,400
Total	2,487,146	2,312,796
Level 1 [Member]
Assets:
Preferred stock	22,067	21,260
Common stock	51,999	45,014
Derivatives	8,804	10,538
Total		76,812
Liabilities:
Total	82,870
Level 2 [Member]
Assets:
Fixed maturities - available for sale	2,395,832	2,442,446
Derivatives	8,386	8,392
Total		2,450,838
Liabilities:
Total	2,404,218
Level 3 [Member]
Assets:
Fixed maturities - available for sale	58	58
Total	2,319,178	58
Liabilities:
Guaranteed residual values of TRAC leases	9,880	9,300
Liabilities from investment contracts	2,295,851	2,290,096
Market risk benefits	13,447	13,400
Total	$ 58	$ 2,312,796