Fair Value Measurements (Carrying and Estimated Fair Values within Fair Value Hierarchy) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Mar. 31, 2022
Assets
Reinsurance recoverables and trade receivables, net	$ 208,182	$ 229,343
Mortgage loans, net	393,980	450,347
Other investments	103,569	120,592
Total	705,731	800,282
Liabilities
Notes, loans and leases payable, gross	5,813,962	5,875,781
Total	5,813,962	5,875,781
Level 1 [Member]
Assets
Reinsurance recoverables and trade receivables, net	0	0
Mortgage loans, net	0	0
Other investments	0	0
Total	0	0
Liabilities
Notes, loans and leases payable, gross	0	0
Total	0	0
Level 2 [Member]
Assets
Reinsurance recoverables and trade receivables, net	0	0
Mortgage loans, net	0	0
Other investments	0	0
Total	0	0
Liabilities
Notes, loans and leases payable, gross	6,236,822	6,059,713
Total	6,236,822	6,059,713
Level 3 [Member]
Assets
Reinsurance recoverables and trade receivables, net	208,182	229,343
Mortgage loans, net	414,886	423,163
Other investments	103,569	120,592
Total	726,637	773,098
Liabilities
Notes, loans and leases payable, gross	0	0
Total	0	0
Carrying Value [Member]
Assets
Reinsurance recoverables and trade receivables, net	208,182	229,343
Mortgage loans, net	414,886	423,163
Other investments	103,569	120,592
Total	726,637	773,098
Liabilities
Notes, loans and leases payable, gross	6,236,822	6,059,713
Total	$ 6,236,822	$ 6,059,713