Percentage of NXT Capital's ordinary shares outstanding held by Stone Point Capital.

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- Definition

Amount of written premiums ceded to other entities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 605
-Section 50
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The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

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- Definition

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

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- Definition

The carrying amount as of the balance sheet date of the known and estimated amounts owed to insurers under reinsurance treaties or other arrangements.

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-Name Accounting Standards Codification
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- Definition

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

+ References

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

Amount of transactions with related party during the financial reporting period.

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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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RELATED PARTY TRANSACTIONS (DETAILS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Unfunded commitments related to other investments		$ 401,000	$ 379,000
Percentage ownership by related parties		45.00%
Ceded premiums		$ 1,217,234	929,064	$ 804,544
Ceded losses and loss expenses		556,000	577,000	401,000
Reinsurance recoverable on unpaid and paid losses		2,334,922	2,096,104
Insurance and reinsurance balances payable		493,183	356,417
Stone Point Group [Member]
Related Party Transaction [Line Items]
Fees paid to related party		4,000	4,000	4,000
NXT Capital [Member]
Related Party Transaction [Line Items]
Fees paid to related party		1,000	1,000	1,000
NXT Capital II [Member]
Related Party Transaction [Line Items]
Unfunded commitments related to other investments		30,000
NXT Capital III [Member]
Related Party Transaction [Line Items]
Unfunded commitments related to other investments		30,000
Chairman [Member]
Related Party Transaction [Line Items]
Fees paid to related party		600	1,000	$ 1,000
Significant influence [Member]
Related Party Transaction [Line Items]
Amounts of transactions with related parties		411,000	$ 193,000
Harrington Re [Member]
Related Party Transaction [Line Items]
Ceded premiums		128,000
Ceded losses and loss expenses		27,000
Reinsurance recoverable on unpaid and paid losses		38,000
Insurance and reinsurance balances payable		86,000
Ventures Re [Member]
Related Party Transaction [Line Items]
Ceded premiums		40,000
Ceded losses and loss expenses		$ 10,000
Scenario, Forecast [Member] \| Chairman [Member]
Related Party Transaction [Line Items]
Fees paid to related party	$ 500