Fair Value Measurements (Carrying and Estimated Fair Values within Fair Value Hierarchy) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022
Assets
Reinsurance recoverables and trade receivables, net	$ 219,574	$ 229,343
Mortgage loans, net	437,604	450,347
Other investments	123,739	120,592
Total	780,917	800,282
Liabilities
Notes, loans and leases payable, gross	5,973,107	5,875,781
Total	5,973,107	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	6,269,352	6,059,713
Total	6,269,352	6,059,713
Level 3 [Member]
Assets
Reinsurance recoverables and trade receivables, net	219,574	229,343
Mortgage loans, net	433,385	423,163
Other investments	123,739	120,592
Total	776,698	773,098
Liabilities
Notes, loans and leases payable, gross	0	0
Total	0	0
Carrying Value [Member]
Assets
Reinsurance recoverables and trade receivables, net	219,574	229,343
Mortgage loans, net	433,385	423,163
Other investments	123,739	120,592
Total	776,698	773,098
Liabilities
Notes, loans and leases payable, gross	6,269,352	6,059,713
Total	$ 6,269,352	$ 6,059,713