v3.2.0.727

Reinsurance (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Mar. 09, 2015	Dec. 31, 2014
Reinsurance Disclosures [Abstract]
Percentage of ceded earned premiums to gross earned premiums	19.00%	19.00%	19.00%	19.00%
Percentage of assumed earned premiums to net earned premiums	32.00%	35.00%	32.00%	36.00%
Reinsurance recoverables	$ 143.3	$ 141.3	$ 232.1	$ 238.9
Total payment under retrospective reinsurance transaction on ceded asbestos and environmental policies					$ 89.0
Cash paid at closing under retrospective reinsurance transaction on ceded asbestos and environmental policies					69.9
Cumulative amount of reserves for losses and loss adjustment expenses on ceded asbestos and environmental policies					94.1
Deferred gain under retrospective reinsurance transaction on ceded asbestos and environmental policies					$ 5.1
Approximate percentage of ceded reserves under retrospective reinsurance transaction to net asbestos and environmental reserves for losses and loss adjustment expenses						35.00%

X

- Definition

The total amount of cash paid at closing under the retrospective reinsurance transaction which ceded a portfolio of policies comprised of liabilities arising from asbestos and environmental exposures.

+ References

No definition available.

+ Details

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- Definition

Ceded reserves as a percentage of net asbestos and environmental reserves for losses and loss adjustment expenses.

+ References

No definition available.

+ Details

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X

- Definition

The cumulative amount of reserves for losses and loss adjustment expenses on ceded asbestos and environmental policies.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

The amount of deferred gain under the retrospective reinsurance transaction on ceded asbestos and environmental policies to be recognized in earnings in future periods in proportion to the actual reinsurance recoveries received pursuant to the transaction.

+ 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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The total payment under the retrospective reinsurance transaction which ceded a portfolio of policies comprised of liabilities arising from asbestos and environmental exposures.

+ References

No definition available.

+ Details

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- Definition

Percentage of assumed premiums earned by the entity to net premiums earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 944



-SubTopic 235



-Section S99



-Paragraph 2



-Subparagraph (SX 210.12-17)



-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

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- References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 944



-SubTopic 20



-Section 50



-Paragraph 3



-URI http://asc.fasb.org/extlink&oid=6480758&loc=d3e6811-158387

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