Ceded Losses

No definition available.

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- Definition

Number of Reinsurers

+ References

No definition available.

+ Details

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- Definition

Percentage of first event coverage

+ References

No definition available.

+ Details

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

- Definition

Reinsurance coverage period

+ References

No definition available.

+ Details

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- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 320
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=28366721&loc=d3e22002-158495

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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- Definition

The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5074-111524

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-Name Accounting Standards Codification
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-Number 210
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

+ Details

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Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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- Definition

The sum for all reinsurance arrangements of the known and estimated amount recoverable as of the balance sheet date from a given reinsurer for claims paid or incurred by the ceding insurer and associated claims settlement expenses for each reinsurance arrangement (or, the sum of all cases determined individually, probably applying different assumptions to each arrangement).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 6
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 6
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Balance Type:	debit
Period Type:	instant

- Definition

Amount after valuation allowance recoverable including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Name Regulation S-X (SX)
-Number 210
-Section 03
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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)		12 Months Ended
Reinsurance (Narrative) (Details)	Jun. 26, 2013 USD ($)	Dec. 31, 2015 USD ($) reinsurer	Dec. 31, 2014 USD ($)	Jan. 30, 2012 USD ($)
Reinsurance [Line Items]
Number of reinsurers \| reinsurer		2
Reinsurance recoverables		$ 7,470,403,000	$ 7,254,585,000
Allowance for doubtful accounts		10,820,000	10,820,000
Invested assets held in trusts		$ 923,512,000	1,022,078,000
First event coverage, percentage		17.00%
Ceded Losses		$ 0
Largest Reinsurance Recoverable Balances
Reinsurance [Line Items]
Reinsurance recoverables		$ 4,607,056,000
January 30, 2012 Ibis Re II Ltd. Agreement
Reinsurance [Line Items]
Reinsurance coverage				$ 130,000,000
Reinsurance coverage period (in years)		3 years
June 26, 2013 Ibis Re II Ltd. Agreement
Reinsurance [Line Items]
Reinsurance coverage	$ 185,000,000
Reinsurance coverage period (in years)	3 years
Ibis Re Ltd. Agreements
Reinsurance [Line Items]
Reinsurance coverage		$ 315,000,000
Hartford
Reinsurance [Line Items]
Reinsurance recoverables		1,053,496,000	1,077,791,000
John Hancock
Reinsurance [Line Items]
Reinsurance recoverables		$ 3,553,560,000	$ 3,471,908,000
Catastrophe Bonds Senior 2012-1 Notes
Reinsurance [Line Items]
Debt instrument, face amount				$ 130,000,000
Catastrophe Bonds Senior 2013-1 Notes
Reinsurance [Line Items]
Debt instrument, face amount	$ 185,000,000