Number of largest company reinsurers

No definition available.

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- Definition

The gross reinsurance recoverable balance of a specified reinsurer or reinsurers as a percentage of the total gross reinsurance recoverable balance at the end of the period.

+ References

No definition available.

+ Details

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- Definition

Percentage of ceded premiums earned by the entity to gross premiums earned.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17(Column F))
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

+ Details

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- Definition

Amount of reduction of provision for policy benefits and costs incurred for policies ceded.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6811-158387

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Reinsurance (Narrative) (Details) $ in Millions	12 Months Ended
Reinsurance (Narrative) (Details) $ in Millions	Dec. 31, 2018 USD ($) reinsurer	Dec. 31, 2017 USD ($) reinsurer	Dec. 31, 2016 USD ($)
Reinsurance Disclosures [Line Items]
Number of largest company reinsurers \| reinsurer		10
Percentage of ceded earned premiums to gross earned premiums	38.00%	21.00%	17.00%
Percentage of assumed earned premiums to net earned premiums	28.00%	30.00%	30.00%
2018 Catastrophes [Member]
Reinsurance Disclosures [Line Items]
Reinsurance recoverables	$ 244.1
2017 Catastrophes [Member]
Reinsurance Disclosures [Line Items]
Reinsurance recoverables		$ 490.3
Underwriting Operations [Member]
Reinsurance Disclosures [Line Items]
Number of largest company reinsurers \| reinsurer	10
Reinsurance recoverables	$ 710.5	$ 856.8	$ 362.0
Underwriting Operations [Member] \| Ten Largest Reinsurers [Member]
Reinsurance Disclosures [Line Items]
Recoverable balances as a percentage of the total balance	61.00%	61.00%
Underwriting Operations [Member] \| Fairfax Financial Group [Member]
Reinsurance Disclosures [Line Items]
Recoverable balances as a percentage of the total balance	9.00%
Program Services [Member]
Reinsurance Disclosures [Line Items]
Number of largest company reinsurers \| reinsurer	10
Reinsurance recoverables	$ 1,300.0
Program Services [Member] \| Ten Largest Reinsurers [Member]
Reinsurance Disclosures [Line Items]
Recoverable balances as a percentage of the total balance	75.00%	79.00%
Program Services [Member] \| Fosun International Holdings, Ltd [Member]
Reinsurance Disclosures [Line Items]
Recoverable balances as a percentage of the total balance	24.00%