Investments (Realized Investment Gains Losses Net) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	$ (2,984)	$ (37,958)	$ (114,615)	$ 79,241
Fixed maturities
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	4,726	10,313	8,772	16,088
Equity securities
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	345	0	343	145
Commercial mortgage and other loans
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	76	5,217	355	4,913
Joint ventures and limited partnerships
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	23	0	188	0
Derivatives
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	(8,156)	(53,489)	(124,318)	58,076
Other
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	$ 2	$ 1	$ 45	$ 19