Fair Value Measurements (Quantitative Information Used As Level 3 Inputs) (Details) - Jun. 30, 2015 - Significant Unobservable Inputs (Level 3) $ in Thousands	USD ($) d	USD ($) d $ / bond
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	$ 359,042	$ 359,042
Corporate \| Discounted Cash Flow Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	7,660	$ 7,660
Corporate \| Discounted Cash Flow Valuation Technique \| Weighted Average or Actual
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Credit spread		3.60%
Liquidity discount		1.00%
Risk-free rate		0.30%
Dividend rate		6.50%
Fixed maturity investments
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	7,660	$ 7,660
Private equity partnerships \| Net Asset Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	$ 250,796	250,796
Private equity partnerships \| Net Asset Valuation Technique \| Low
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance	(30.20%)
Private equity partnerships \| Net Asset Valuation Technique \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance	14.00%
Private equity partnerships \| Net Asset Valuation Technique \| Weighted Average or Actual
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance	3.10%
Senior secured bank loan funds \| Net Asset Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	$ 22,561	22,561
Senior secured bank loan funds \| Net Asset Valuation Technique \| Weighted Average or Actual
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance	1.20%
Hedge funds \| Net Asset Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	$ 2,338	2,338
Hedge funds \| Net Asset Valuation Technique \| Low
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance	0.00%
Hedge funds \| Net Asset Valuation Technique \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance	0.00%
Hedge funds \| Net Asset Valuation Technique \| Weighted Average or Actual
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance	0.00%
Other Investments
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	$ 275,695	275,695
Reinsurance deposit asset \| Internal Valuation Model Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	82,905	$ 82,905
Reinsurance deposit asset \| Internal Valuation Model Valuation Technique \| Weighted Average or Actual
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Estimated performance		3.00%
Assumed reinsurance contract \| Internal Valuation Model Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liabilities, fair value	(1,308)	$ (1,308)
Assumed reinsurance contract \| Internal Valuation Model Valuation Technique \| Low
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Bond price \| $ / bond		96.23
Assumed reinsurance contract \| Internal Valuation Model Valuation Technique \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Bond price \| $ / bond		99.78
Assumed reinsurance contract \| Internal Valuation Model Valuation Technique \| Weighted Average or Actual
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Bond price \| $ / bond		97.48
Liquidity premium		1.30%
Assumed and ceded (re)insurance contract \| Internal Valuation Model Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liabilities, fair value	$ (5,896)	$ (5,896)
Assumed and ceded (re)insurance contract \| Internal Valuation Model Valuation Technique \| Low
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Contract period \| d	194	194
Assumed and ceded (re)insurance contract \| Internal Valuation Model Valuation Technique \| Maximum
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Contract period \| d	1,100	1,100
Assumed and ceded (re)insurance contract \| Internal Valuation Model Valuation Technique \| Weighted Average or Actual
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Net undiscounted cash flows		$ (9,233)
Expected loss ratio		28.00%
Net acquisition expense ratio		14.00%
Contract period \| d	824	824
Discount rate		1.00%
Assumed and ceded (re)insurance contracts \| Internal Valuation Model Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	$ 75,701	$ 75,701
Weather contract \| Internal Valuation Model Valuation Technique
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liabilities, fair value	$ (14)	$ (14)

Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]

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Fair Value Inputs, Bond Price

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Fair Value Inputs, Contract Period

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

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Fair Value Inputs, Expected Loss Ratio

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Fair Value Inputs, Liquidity Premium

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Fair Value Inputs, Net Acquisition Expense Ratio

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Fair Value Inputs, Net Undiscounted Cash Flows

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- Definition

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.

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- Definition

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).

+ References

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

-Publisher FASB

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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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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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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.

+ References

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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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