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Estimated percentage return for the period on fair value at beginning of period.

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No definition available.

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This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

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Risk-free interest rate assumption used in valuing an instrument.

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Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

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Risk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.

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Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity.

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No definition available.

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Fair Value Measurements (Quantitative Information Used As Level 3 Inputs) (Details) (USD $) In Thousands, unless otherwise specified					6 Months Ended				6 Months Ended				6 Months Ended		6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Significant Unobservable Inputs (Level 3)	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Corporate Discounted Cash Flow Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Corporate Discounted Cash Flow Valuation Technique Weighted Average or Actual	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Corporate Internal Valuation Model Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Fixed maturity investments	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Private equity partnerships Net Asset Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Private equity partnerships Net Asset Valuation Technique Low	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Private equity partnerships Net Asset Valuation Technique Maximum	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Private equity partnerships Net Asset Valuation Technique Weighted Average or Actual	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Senior secured bank loan funds Net Asset Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Senior secured bank loan funds Net Asset Valuation Technique Weighted Average or Actual	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Hedge funds Net Asset Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Hedge funds Net Asset Valuation Technique Low	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Hedge funds Net Asset Valuation Technique Maximum	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Hedge funds Net Asset Valuation Technique Weighted Average or Actual	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Other Investments	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Weather Contract Internal Valuation Model Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Private equity partnerships Net Asset Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Senior secured bank loan funds Net Asset Valuation Technique	Jun. 30, 2014 Significant Unobservable Inputs (Level 3) Hedge funds Net Asset Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value			$ 381,396	$ 15,938		$ 30,238	$ 46,176	$ 314,983				$ 15,976		$ 3,190				$ 334,149		$ 314,983	$ 15,976	$ 3,190
Liabilities, fair value			1,071																(1,149)
Derivative Asset	$ 9,946	$ 10,667
Credit spread					1.10%
Liquidity discount					1.00%
Risk-free rate					0.30%
Dividend rate					6.20%
Estimated performance									(3.00%)	18.90%	4.00%		0.70%		0.00%	0.00%	0.00%