Property and casualty insurance revenues derived from customers of foreign countries.

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- Definition

Property and casualty insurance revenues derived from customers of foreign countries by subsidiary

+ References

No definition available.

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- Definition

Favorable prior year reserve development of the Company's liability for losses and loss adjustment expenses related to certain lines of business within subsidiaries including exited and ongoing lines of business in connection with a reinsurance to close agreement.

+ References

No definition available.

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- Definition

Special charges related to the exit of certain lines of business within subsidiaries.

+ References

No definition available.

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- Definition

Special charges to increase asbestos and environmental reserves

+ References

No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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-Section 45
-Paragraph 28
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- Definition

Amount, after effects of reinsurance, of expense for claims incurred and costs incurred in the claim settlement process attributable to asbestos and environmental claims.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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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

No definition available.

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Segments of Operations - Narrative (Details) $ in Millions	3 Months Ended				12 Months Ended
Segments of Operations - Narrative (Details) $ in Millions	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of segments \| segment					3
Revenue derived from sales of property and casualty insurance outside of the United States					7.00%	7.00%	5.00%
Property and casualty insurance \| Other lines
Segment Reporting Information [Line Items]
Percent of foreign sales attributable to Neon					66.67%
Special A&E charges		$ 18	$ 18		$ 18	$ 18	$ 89
Special charges related to the exit of certain lines of business within subsidiaries	$ 76
Other
Segment Reporting Information [Line Items]
Loss on the retirement of debt					5		51
Special charges to increase asbestos and environmental reserves					11	9	24
Special A&E charges
Segment Reporting Information [Line Items]
Special A&E charges					18	$ 18	89
Special A&E charges \| Property and casualty insurance \| Other lines
Segment Reporting Information [Line Items]
Special A&E charges					18		89
Neon Capital Limited \| Property and casualty insurance
Segment Reporting Information [Line Items]
Favorable reserve development related to certain lines of business within subsidiaries in connection with a reinsurance to close agreement				$ 42
Neon Capital Limited \| Property and casualty insurance \| Other lines
Segment Reporting Information [Line Items]
Special charges related to the exit of certain lines of business within subsidiaries					$ 76
Favorable reserve development related to certain lines of business within subsidiaries in connection with a reinsurance to close agreement				$ 18			$ 18