Investments (All Other Net Unrealized Investment Gains and Losses in AOCI) (Details) (USD $) In Thousands, unless otherwise specified			6 Months Ended
	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 Accumulated Other Comprehensive Income (loss) [Member]		Jun. 30, 2013 Accumulated Net Unrealized Investment Gain (Loss) Pre Tax [Member]		Jun. 30, 2013 Deferred Costs Policy Acquisition And Sales Inducements And Valuation Of Business Acquired, Pre Tax [Member]		Jun. 30, 2013 Policyholders Account Balances Pre Tax [Member]		Jun. 30, 2013 Deferred Income Tax Liability Benefit [Member]		Jun. 30, 2013 Accumulated Net Unrealized Investment Gain (Loss) [Member]		Jun. 30, 2013 Other Net Unrealized Investment Gains and Losses [Member] Accumulated Other Comprehensive Income (loss) [Member]		Jun. 30, 2013 Other Net Unrealized Investment Gains and Losses [Member] Accumulated Net Unrealized Investment Gain (Loss) Pre Tax [Member]		Jun. 30, 2013 Other Net Unrealized Investment Gains and Losses [Member] Deferred Costs Policy Acquisition And Sales Inducements And Valuation Of Business Acquired, Pre Tax [Member]		Jun. 30, 2013 Other Net Unrealized Investment Gains and Losses [Member] Policyholders Account Balances Pre Tax [Member]		Jun. 30, 2013 Other Net Unrealized Investment Gains and Losses [Member] Deferred Income Tax Liability Benefit [Member]		Jun. 30, 2013 Other Net Unrealized Investment Gains and Losses [Member] Accumulated Net Unrealized Investment Gain (Loss) [Member]
Balance	$ 87,954	$ 267,461			$ (618)		$ 295		$ 563		$ (115)		$ 125				$ 505,100	[1],[2]	$ (220,208)		$ 125,833		$ (143,646)		$ 267,079
Net investment gains (losses) on investments arising during the period					527		0		0		(184)		343				(282,559)	[1]	0		0		98,896		(183,663)
Reclassification adjustment for (gains) losses included in net income																	(38,879)	[2]	0		0		13,608		(25,271)
Reclassification adjustment for OTTI losses excluded from net income					3	[3]	0	[3]	0	[3]	(1)	[3]	2	[3]	(3)	[2]			0	[4]	0	[4]	1	[4]	(2)	[4]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs					0		(2,437)		0		853		(1,584)				0	[2]	152,905		0		(53,517)		99,388
Impact of net unrealized investment (gains) losses on policyholders' account balance			0	[2]	0		0		313		(110)		203						0		(109,266)		38,243		(71,023)
Balance	$ 87,954	$ 267,461			$ 3,282		$ (2,142)		$ 876		$ (737)		$ 1,279				$ 183,659	[2]	$ (67,303)		$ 16,567		$ (46,415)		$ 86,508

[1] Includes credit-tranched securities collateralized by sub-prime mortgages, auto loans, credit cards, education loans, and other asset types.

[2] Includes cash flow hedges. See Note 5 for information on cash flow hedges.

[3] Represents “transfers in” related to the portion of OTTI losses recognized during the period that were not recognized in earnings for securities with no prior OTTI loss.

[4] Represents “transfers out” related to the portion of OTTI losses recognized during the period that were not recognized in earnings for securities with no prior OTTI loss.