Investments (Fair Value Below Amortized Cost of Gross Unrealized Losses for Fixed Maturity and Equity Securities) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Gross unrealized losses with number of securities [Line Items]
Available-for-sale Securities, Gross Unrealized Losses	$ 134,919	$ 324,600
Percentage Of Total Gross Unrealized Losses	100.00%	100.00%
Less Than 20 Percent [Member]
Gross unrealized losses with number of securities [Line Items]
Available-for-sale Securities, Gross Unrealized Losses	111,965	296,731
Percentage Of Total Gross Unrealized Losses	83.00%	91.40%
More Than Or Equal To 20 Percent For Less Than Six Months [Member]
Gross unrealized losses with number of securities [Line Items]
Available-for-sale Securities, Gross Unrealized Losses	13,698	6,444
Percentage Of Total Gross Unrealized Losses	10.10%	2.00%
More Than Or Equal To 20 Percent For Six Months Or Greater [Member]
Gross unrealized losses with number of securities [Line Items]
Available-for-sale Securities, Gross Unrealized Losses	$ 9,256	$ 21,425
Percentage Of Total Gross Unrealized Losses	6.90%	6.60%