Accumulated Other Comprehensive Income (Schedule of Reclassifications out of AOCI) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Investment related gains (losses), net	$ 119,397		$ 58,352		$ 204,271		$ 152,925
Investment income	410,607		444,234		814,982		869,365
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	300,535		(74,758)		499,975		204,069
Tax (expense) benefit	(102,239)		25,146		(165,015)		(68,146)
Net income (loss)	198,296		(49,612)		334,960		135,923
Unrealized Appreciation Depreciation Of Investments [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	31,833		428		37,661		9,533
Tax (expense) benefit	(11,059)		(87)		(12,963)		(3,021)
Net income (loss)	20,774		341		24,698		6,512
Unrealized Appreciation Depreciation Of Investments [Member] | Unrealized Gains Losses On Available For Sale Securities [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Investment related gains (losses), net	27,142		13,510		28,331		23,858
Unrealized Appreciation Depreciation Of Investments [Member] | Gains Losses On Qualifying Cash Flow Hedging Instruments [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Investment income	321		201		539		506
Unrealized Appreciation Depreciation Of Investments [Member] | DAC Attributed To Unrealized Gains Losses [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Deferred policy acquisition costs attributed to unrealized gains and losses	4,370	[1]	(13,283)	[1]	8,791	[1]	(14,831)	[1]
Amortization Of Unrealized Pension And Postretirement Benefits [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	(678)		(1,181)		(1,570)		(2,298)
Tax (expense) benefit	238		413		550		804
Net income (loss)	(440)		(768)		(1,020)		(1,494)
Amounts Reclassified From AOCI [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	20,334		(427)		23,678		5,018
Prior Service Cost [Member] | Amortization Of Unrealized Pension And Postretirement Benefits [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Prior service cost	(216)	[2]	(213)	[2]	(218)	[2]	(307)	[2]
Actuarial Gains Losses [Member] | Amortization Of Unrealized Pension And Postretirement Benefits [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Actuarial gains/(losses)	$ (462)	[2]	$ (968)	[2]	$ (1,352)	[2]	$ (1,991)	[2]

[1] This AOCI component is included in the computation of the deferred policy acquisition cost. See Note 8 – “Deferred Policy Acquisition Costs” of the 2013 Annual Report for additional details.

[2] These AOCI components are included in the computation of the net periodic pension cost. See Note 9 – “Employee Benefit Plans” for additional details.