Derivative Instruments (Financial Statement Classification and Impact of Derivatives Used in Qualifying and Non-qualifying Hedge Relationships) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net					$ 4,700
Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	(5,547)		(72,935)		(10,791)		(162,600)
Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	(3)		(17)		(20)		(68)
Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	127		(53)		118		19
Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	5,080	[1]	(2,781)	[1]	4,657	[1]	(438)	[1]
Cash Flow Hedging [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Cash Flow Hedging [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	(3)		(17)		(20)		(68)
Cash Flow Hedging [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	80		(30)		63		2
Cash Flow Hedging [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	5,080	[1]	(2,781)	[1]	4,657	[1]	(438)	[1]
Cash Flow Hedging [Member] | Cross Currency Interest Rate Contract [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Cash Flow Hedging [Member] | Cross Currency Interest Rate Contract [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	(3)		(17)		(20)		(68)
Cash Flow Hedging [Member] | Cross Currency Interest Rate Contract [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	80		(30)		63		2
Cash Flow Hedging [Member] | Cross Currency Interest Rate Contract [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	5,080	[1]	(2,781)	[1]	4,657	[1]	(438)	[1]
Nondesignated [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	(5,547)		(72,935)		(10,791)		(162,600)
Nondesignated [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	47		(23)		55		17
Nondesignated [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0	[1]	0	[1]	0	[1]	0	[1]
Nondesignated [Member] | Interest Rate Contract [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	14,059		(11,810)		77,657		(94,040)
Nondesignated [Member] | Interest Rate Contract [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Interest Rate Contract [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Interest Rate Contract [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0	[1]	0	[1]	0	[1]	0	[1]
Nondesignated [Member] | Foreign Exchange Contract [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Foreign Exchange Contract [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Foreign Exchange Contract [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Foreign Exchange Contract [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0	[1]	0	[1]	0	[1]	0	[1]
Nondesignated [Member] | Cross Currency Interest Rate Contract [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	3,546		(2,137)		3,332		(353)
Nondesignated [Member] | Cross Currency Interest Rate Contract [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Cross Currency Interest Rate Contract [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	47		(23)		55		17
Nondesignated [Member] | Cross Currency Interest Rate Contract [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0	[1]	0	[1]	0	[1]	0	[1]
Nondesignated [Member] | Credit Risk Contract [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		(28)		(11)		(86)
Nondesignated [Member] | Credit Risk Contract [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Credit Risk Contract [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Credit Risk Contract [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0	[1]	0	[1]	0	[1]	0	[1]
Nondesignated [Member] | Equity Contract [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	414		(14,507)		(15,568)		(55,934)
Nondesignated [Member] | Equity Contract [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Equity Contract [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Equity Contract [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0	[1]	0	[1]	0	[1]	0	[1]
Nondesignated [Member] | Embedded Derivative [Member] | Net Realized Investments Gain Loss [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	(23,566)		(44,453)		(76,201)		(12,187)
Nondesignated [Member] | Embedded Derivative [Member] | Net Investment Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Embedded Derivative [Member] | Other Income [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	0		0		0		0
Nondesignated [Member] | Embedded Derivative [Member] | Accumulated Other Comprehensive Income (loss) [Member]
Derivative Instruments Gain Loss [Line Items]
Derivative Instruments Gain (Loss) Recognized In Income Net	$ 0	[1]	$ 0	[1]	$ 0	[1]	$ 0	[1]

[1] (1) Amounts deferred in “Accumulated other comprehensive income (loss).”