Reinsurance and Policy Benefits and Losses, Claims and Loss Expenses Payable (Insurance Subsidiaries Activity) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2022
Year ended December 31,
Net amount (a)	$ 89,745	$ 99,149	$ 111,027
Life Insurance [Member]
Year ended December 31,
Direct amount (a) - Life insurance in force	909,894	970,454	1,029,537
Ceded to other companies - Life insurance in force	48	48	72
Assumed from other companies - Life insurance in force	278,445	304,891	328,030
Net amount (a) - Life insurance in force	$ 1,188,291	$ 1,275,297	$ 1,357,495
Percentage of amount assumed to net - Life insurance in force	23.00%	24.00%	24.00%
Direct amount (a)	$ 179,467	$ 189,974	$ 194,849
Ceded to Other Companies	96	153	162
Assumed from Other Companies	5,176	5,570	6,007
Net amount (a)	184,547	195,391	200,694
Premiums earned: Life [Member] \| Life Insurance [Member]
Year ended December 31,
Direct amount (a)	49,184	52,298	56,353
Ceded to Other Companies	1	1	2
Assumed from Other Companies	4,183	4,181	4,514
Net amount (a)	$ 53,366	$ 56,478	$ 60,865
Percentage of amount assumed to net	8.00%	7.00%	7.00%
Premiums earned: Accident and health [Member] \| Life Insurance [Member]
Year ended December 31,
Direct amount (a)	$ 35,324	$ 41,354	$ 48,385
Ceded to Other Companies	95	152	160
Assumed from Other Companies	844	983	1,166
Net amount (a)	$ 36,073	$ 42,185	$ 49,391
Percentage of amount assumed to net	2.00%	2.00%	2.00%
Premiums earned: Annuity [Member] \| Life Insurance [Member]
Year ended December 31,
Direct amount (a)	$ 157	$ 80	$ 444
Ceded to Other Companies
Assumed from Other Companies	149	406	327
Net amount (a)	$ 306	$ 486	$ 771
Percentage of amount assumed to net	49.00%	84.00%	42.00%
Premiums earned: Property and casualty [Member] \| Life Insurance [Member]
Year ended December 31,
Direct amount (a)	$ 94,802	$ 96,242	$ 89,667
Ceded to Other Companies
Assumed from Other Companies
Net amount (a)	$ 94,802	$ 96,242	$ 89,667
Percentage of amount assumed to net

Amount of life insurance issued and outstanding assumed from other entity, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Paragraph Column D
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column D))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

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Amount of life insurance issued and outstanding ceded to other entity, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Paragraph Column C
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column C))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

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- Definition

Amount, before effect of reinsurance, of life insurance issued and outstanding, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Paragraph Column B
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column B))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

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Amount, after effect of reinsurance, of life insurance issued and outstanding, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Paragraph Column E
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column E))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

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Percentage of assumed life insurance contract issued and outstanding to life insurance contract issued and outstanding after effect of reinsurance, as disclosed in supplementary reinsurance information. Includes, but is not limited to, dividend and adjustment to face value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 17
-Paragraph Column F
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column F))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

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Represents the monetary amount of direct premiums earned (unearned) during the indicated time period.

+ References

No definition available.

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Represents the monetary amount of ceded premiums earned (unearned) during the indicated time period.

+ References

No definition available.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column B))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479655/944-605-50-1

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- Definition

Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column E))
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-URI https://asc.fasb.org//1943274/2147480149/944-235-S99-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479655/944-605-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Topic 942
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 944
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

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Percentage of assumed premium earned to premium earned after effects of reinsurance, as disclosed in supplementary reinsurance information.

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