Amount, after effects of reinsurance, of expense (reversal of expense) for other claims incurred in prior reporting periods and related claims settlement costs, excluding asbestos related claims.

No definition available.

+ Details

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- Definition

The increase (decrease) during the reporting period in asbestos and environmental claims reserve, before estimated recoveries from reinsurers.

+ 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),(c)
-URI http://asc.fasb.org/extlink&oid=99382578&loc=d3e14764-158437

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- 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

No definition available.

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- Definition

Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=99382578&loc=d3e14764-158437

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Reserves for unpaid losses and loss adjustment expenses - By segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reserves for unpaid losses and loss adjustment expenses
Unfavorable (favorable) loss reserve development	$ (10.1)	$ (3.4)	$ (23.0)	$ 4.1
Global Property
Reserves for unpaid losses and loss adjustment expenses
Unfavorable (favorable) loss reserve development	10.8	0.4	28.7	(1.6)
Global Property \| Natural catastrophes
Reserves for unpaid losses and loss adjustment expenses
Unfavorable (favorable) loss reserve development			(7.4)
Global A&H
Reserves for unpaid losses and loss adjustment expenses
Unfavorable (favorable) loss reserve development	(3.0)	0.4	(11.4)	(4.3)
Specialty & Casualty
Reserves for unpaid losses and loss adjustment expenses
Unfavorable (favorable) loss reserve development	(7.3)	(3.3)	(17.7)	(9.2)
Aviation & Space
Reserves for unpaid losses and loss adjustment expenses
Unfavorable (favorable) loss reserve development			12.0
Runoff & Other
Reserves for unpaid losses and loss adjustment expenses
Unfavorable (favorable) loss reserve development	$ (10.6)	$ (0.9)	$ (22.6)	19.2
Increase (decrease) in asbestos claims reserves				59.3
Unfavorable (favorable) other claims loss reserve development				$ (40.1)