Prior Year Claims And Claims Adjustment Expense, Increase (Decrease) Due To Change In Premium Earnings Estimates

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- Definition

Prior Year Claims And Claims Adjustment Expense, Increase (Decrease) Due To Change In Reserve Estimates

+ References

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- Definition

Underwriting Income (loss), Increase (Decrease)

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8672-108599

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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.

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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=116884095&loc=d3e14764-158437

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Loss and loss adjustment expense reserves - Narrative (Details) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2021 segment	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Increase (decrease) in prior years' reserves		$ (42.6)	$ 33.8	$ (86.5)
Increase (decrease) in loss reserves resulting from a change in premium earnings estimates			18.8	12.0
Increase (decrease) in loss reserves resulting from a change in loss reserve estimates			15.0	(98.5)
Increase (decrease) in net underwriting results			$ (30.5)	$ 3.7
Number of operating segments \| segment	2	2
Corporate
Segment Reporting Information [Line Items]
Increase (decrease) in prior years' reserves		$ (10.5)
Reinsurance \| Operating Segments
Segment Reporting Information [Line Items]
Increase (decrease) in prior years' reserves		(18.6)
Insurance & Services \| Operating Segments
Segment Reporting Information [Line Items]
Increase (decrease) in prior years' reserves		$ (13.5)