Fair Value Measurements (Quantitative Information Used As Level 3 Inputs) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($) $ / bond	Dec. 31, 2015 USD ($)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Other assets and (liabilities)	$ 5,804	$ 3,463
Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, fair value	(12,012)
Other assets and (liabilities)	(12,012)
Assumed reinsurance contract | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liabilities, fair value	$ (677)
Assumed reinsurance contract | Low | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Bond price | $ / bond	100.01
Assumed reinsurance contract | Maximum | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Bond price | $ / bond	102.95
Assumed reinsurance contract | Weighted Average or Actual | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Bond price | $ / bond	101.57
Liquidity discount	1.30%
Assumed and ceded (re)insurance contract | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liabilities, fair value	$ (11,335)
Assumed and ceded (re)insurance contract | Low | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Contract period	8 months 1 day
Assumed and ceded (re)insurance contract | Maximum | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Contract period	4 years 7 months 27 days
Assumed and ceded (re)insurance contract | Weighted Average or Actual | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Net undiscounted cash flows	$ (11,520)
Expected loss ratio	39.00%
Net acquisition expense ratio	(21.70%)
Contract period	4 years 4 months 6 days
Discount rate	1.10%
Assumed and ceded (re)insurance contracts | Internal Valuation Model Valuation Technique | Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Liabilities, fair value	$ (12,012)