Fair Value Measurements (Carrying and Estimated Fair Values within Fair Value Hierarchy) (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Mar. 31, 2025
Assets
Receivables, Fair Value Disclosure	$ 140,467	$ 195,710
Mortgage loans, net	695,362	639,162
Other investments	12,521	11,868
Total	848,350	846,740
Liabilities
Notes, loans and leases payable, gross	7,462,822	6,703,510
Liabilities from investment contracts	2,406,345	2,436,537
Total	9,869,167	9,140,047
Level 2 [Member]
Liabilities
Notes, loans and leases payable, gross	7,462,822	6,703,510
Total	7,462,822	6,703,510
Level 3 [Member]
Assets
Receivables, Fair Value Disclosure		195,710
Mortgage loans, net		639,162
Other investments		11,868
Total		846,740
Liabilities
Liabilities from investment contracts	2,406,345	2,436,537
Total	2,406,345	2,436,537
Carrying Value [Member]
Assets
Receivables, Fair Value Disclosure	140,467	195,710
Mortgage loans, net	699,878	657,567
Other investments	12,521	11,868
Total	852,866	865,145
Liabilities
Notes, loans and leases payable, gross	8,058,179	7,229,341
Liabilities from investment contracts	2,444,359	2,502,729
Total	$ 10,502,538	$ 9,732,070