Fair Value of Assets and Liabilities (Changes in Level 3 Assets and Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Debt Securities [Member] | Corporate Debt Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	$ 95,555		$ 89,658
Included In Earnings
Realized investment gains (losses), net	4		7
Asset management fees and other income	0		0
Included in other comprehensive income (loss)	(271)		(856)
Net investment income	1,154		1,228
Purchases	600		2,625
Sales	0		0
Issuances	0		2,775
Settlements	(1,467)		(4,298)
Other			0	[1]
Transfers into Level 3	0	[2]	11,991
Transfers out of Level 3	0	[3]	0	[2]
Fair Value, end of period	95,575		103,130
Included In Earnings
Realized investment gains (losses), net	0	[3]	0
Asset management fees and other income	0	[3]	0
Interest credited to policyholders' account balances	0	[3]	0
Debt Securities [Member] | Asset-backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	69,298		48,563
Included In Earnings
Realized investment gains (losses), net	0		0
Asset management fees and other income	0		0
Included in other comprehensive income (loss)	162		862
Net investment income	135		158
Purchases	7,058		0
Sales	0		0
Issuances	0		0
Settlements	(3,913)		(2,883)
Other			0	[1]
Transfers into Level 3	0	[2]	0
Transfers out of Level 3	0	[2]	0	[2]
Fair Value, end of period	72,740		46,700
Included In Earnings
Realized investment gains (losses), net	0	[3]	0
Asset management fees and other income	0	[3]	0
Interest credited to policyholders' account balances	0	[3]	0
Debt Securities [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	0
Included In Earnings
Realized investment gains (losses), net	0
Asset management fees and other income	0
Included in other comprehensive income (loss)	0
Net investment income	17
Purchases	9,090
Sales	0
Issuances	0
Settlements	0
Transfers into Level 3	0	[2]
Transfers out of Level 3	0	[2]
Fair Value, end of period	9,107
Included In Earnings
Realized investment gains (losses), net	0	[3]
Asset management fees and other income	0	[3]
Interest credited to policyholders' account balances	0	[3]
Other Long-term Investments [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	1,054		1,213
Included In Earnings
Realized investment gains (losses), net	(624)		(977)
Asset management fees and other income	33		13
Included in other comprehensive income (loss)	0		0
Net investment income	0		0
Purchases	0		0
Sales	0		0
Issuances	0		0
Settlements	0		7
Other			0	[1]
Transfers into Level 3	0	[2]	0
Transfers out of Level 3	0	[2]	0	[2]
Fair Value, end of period	463		256
Included In Earnings
Realized investment gains (losses), net	(624)	[3]	(874)
Asset management fees and other income	33	[3]	13
Interest credited to policyholders' account balances	0	[3]	0
Trading Account Assets Supporting Insurance Liabilities [Member] | Equity Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	207
Included In Earnings
Realized investment gains (losses), net	0
Asset management fees and other income	60
Included in other comprehensive income (loss)	0
Net investment income	0
Purchases	0
Sales	0
Issuances	0
Settlements	0
Transfers into Level 3	0	[2]
Transfers out of Level 3	0	[2]
Fair Value, end of period	267
Included In Earnings
Realized investment gains (losses), net	0	[3]
Asset management fees and other income	61	[3]
Interest credited to policyholders' account balances	0	[3]
Trading Asset [Member] | Equity Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period			203
Included In Earnings
Realized investment gains (losses), net			0
Asset management fees and other income			(2)
Included in other comprehensive income (loss)			0
Net investment income			0
Purchases			0
Sales			0
Issuances			0
Settlements			0
Other			0	[1]
Transfers into Level 3			0	[2]
Transfers out of Level 3			0	[2]
Fair Value, end of period			201
Included In Earnings
Realized investment gains (losses), net			0	[3]
Asset management fees and other income			(1)	[3]
Interest credited to policyholders' account balances			0	[3]
Other Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	1,995
Included In Earnings
Realized investment gains (losses), net	0
Asset management fees and other income	0
Included in other comprehensive income (loss)	5
Net investment income	0
Purchases	0
Sales	0		0
Issuances	0
Settlements	0
Transfers into Level 3	0	[2]
Transfers out of Level 3	0	[2]
Fair Value, end of period	2,000
Included In Earnings
Realized investment gains (losses), net	0	[3]
Asset management fees and other income	0	[3]
Interest credited to policyholders' account balances	0	[3]
Future Policy Benefits [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	(1,793,136)		(1,783,595)
Included In Earnings
Realized investment gains (losses), net	623,786		621,492
Asset management fees and other income	0
Included in other comprehensive income (loss)	0
Net investment income	0
Purchases	0		0
Sales	0
Issuances	(60,973)		(58,447)
Settlements	0
Transfers into Level 3	0	[2]	0	[2]
Transfers out of Level 3	0	[2]	0	[2]
Fair Value, end of period	(1,230,323)		(1,220,550)
Included In Earnings
Realized investment gains (losses), net	613,833	[3]	608,066
Asset management fees and other income	0	[3]	0
Interest credited to policyholders' account balances	0	[3]	0
Reinsurance Recoverable [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, beginning of period	1,732,094		1,747,757
Included In Earnings
Realized investment gains (losses), net	(598,821)		(598,252)
Asset management fees and other income	0		0
Included in other comprehensive income (loss)	0		0
Net investment income	0		0
Purchases	58,136		55,757
Sales	0		0
Issuances	0		0
Settlements	0		0
Other			0	[1]
Transfers into Level 3	0	[2]	0
Transfers out of Level 3	0	[2]	0	[2]
Fair Value, end of period	1,191,409		1,205,262
Included In Earnings
Realized investment gains (losses), net	(588,859)	[3]	(585,098)
Asset management fees and other income	0	[3]	0
Interest credited to policyholders' account balances	$ 0	[3]	$ 0

[1]   (3) Other primarily represents reclasses of certain assets between reporting categories.

[2]   (1) Transfers into or out of Level 3 are generally reported as the value as of the beginning of the quarter in which the transfer occurs.

[3]   (2) Unrealized gains or losses related to assets still held at the end of the period do not include amortization or accretion of premiums and discounts.