Investments (All Other Net Unrealized Investment Gains and Losses in AOCI) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011		Dec. 31, 2010
Balance	$ 147,287	$ 160,712	[1]
Other Net Unrealized Investment Gains and Losses [Member] | Accumulated Net Unrealized Investment Gain (Loss) Pre Tax [Member]
Balance	441,677	504,664		451,879
Cumulative impact of adoption of new authoriative guidance January 2009				0
Net investment gains (losses) on investments arising during the period	(42,295)	19,706		87,097
Reclassification adjustment for (gains) losses included in net income	(22,605)	(82,693)		(34,323)
Reclassification adjustment for OTTI losses excluded from net income		0	[2]	11	[2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs	0	0		0
Impact of net unrealized investment (gains) losses on policyholders' account balance	0
Balance	376,777	441,677		504,664
Other Net Unrealized Investment Gains and Losses [Member] | Deferred Costs Policy Acquisition And Sales Inducements And Valuation Of Business Acquired, Pre Tax [Member]
Balance	(192,119)	(206,046)		(242,840)
Cumulative impact of adoption of new authoriative guidance January 2009				16,957
Net investment gains (losses) on investments arising during the period	0	0		0
Reclassification adjustment for (gains) losses included in net income	0	0		0
Reclassification adjustment for OTTI losses excluded from net income		0	[2]	0	[2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs	45,030	13,927		19,837
Impact of net unrealized investment (gains) losses on policyholders' account balance	0
Balance	(147,089)	(192,119)		(206,046)
Other Net Unrealized Investment Gains and Losses [Member] | Policyholders Account Balances Pre Tax [Member]
Balance		0		0
Cumulative impact of adoption of new authoriative guidance January 2009				0
Net investment gains (losses) on investments arising during the period	0	0		0
Reclassification adjustment for (gains) losses included in net income	0	0		0
Reclassification adjustment for OTTI losses excluded from net income		0	[2]	0	[2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs	0	0		0
Impact of net unrealized investment (gains) losses on policyholders' account balance	(2,164)
Balance	(2,164)			0
Other Net Unrealized Investment Gains and Losses [Member] | Deferred Income Tax Liability Benefit [Member]
Balance	(88,181)	(105,352)		(74,007)
Cumulative impact of adoption of new authoriative guidance January 2009				(5,929)
Net investment gains (losses) on investments arising during the period	14,804	(6,897)		(30,485)
Reclassification adjustment for (gains) losses included in net income	7,912	28,947		12,013
Reclassification adjustment for OTTI losses excluded from net income		0	[2]	(4)	[2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs	(15,760)	(4,879)		(6,940)
Impact of net unrealized investment (gains) losses on policyholders' account balance	757
Balance	(80,468)	(88,181)		(105,352)
Other Net Unrealized Investment Gains and Losses [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]
Balance	161,377	193,266		135,032
Cumulative impact of adoption of new authoriative guidance January 2009				11,028
Net investment gains (losses) on investments arising during the period	(27,491)	12,809		56,612
Reclassification adjustment for (gains) losses included in net income	(14,693)	(53,746)		(22,310)
Reclassification adjustment for OTTI losses excluded from net income		0	[2]	7	[2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs	29,270	9,048		12,897
Impact of net unrealized investment (gains) losses on policyholders' account balance	(1,407)
Balance	$ 147,056	$ 161,377		$ 193,266

[1] “As previously reported” column represents balances reported in the Annual Report on Form 10-K for the year ended December 31, 2011, originally filed with the U.S. Securities and Exchange commission (“SEC”) on March 9, 2012. “As currently reported” column was included in the 8-K filed with the SEC on November 28, 2012.

[2] Includes cash flow hedges. See Note 11 for additional discussion of our cash flow hedges.