Investments (Realized Investment Gains Losses Net) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	$ (68,980)	$ (60,640)	$ (150,491)	$ (61,563)
Fixed Maturities [Member]
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	3,908	2,056	11,716	15,912
Equity Securities [Member]
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	1	703	2	703
Commercial Mortgage Loans [Member]
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	52	(483)	420	(588)
Derivative [Member]
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	(72,935)	(62,916)	(162,600)	(77,590)
Other [Member]
Schedule Of Gain Loss On Investments [Line Items]
Realized investment gains (losses), net	$ (6)	$ 0	$ (29)	$ 0