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Other Comprehensive Income (Loss) (Reclassifications out of Accumulated Other Comprehensive Loss) (Parenthetical) (Details) - Defined Benefit Pension and Postretirement Plans [Member]	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Condensed Statement Of Income Captions [Line Items]
Loss adjustment expenses	40.00%	40.00%	40.00%	40.00%
Percentage of other operating expenses	60.00%	60.00%	60.00%	60.00%

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 04
-Paragraph a
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481231/810-10-45-11

+ Details

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- Definition

Percentage of amounts reclassified from AOCI for pension and post retirement benefits allocated to loss adjustment expenses.

+ References

No definition available.

+ Details

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X

- Definition

Percentage of amounts reclassified from AOCI for pension and post retirement benefits allocated to other operating expenses.

+ References

No definition available.

+ Details

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- Details

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