Investments (Net Investment Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 53,026	$ 73,352	$ 173,970	$ 220,497
Less: investment expenses	(1,705)	(1,981)	(5,176)	(6,056)
Net Investment Income, Total	51,321	71,371	168,794	214,441
Available For Sale Fixed Maturities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	45,868	59,419	148,402	190,400
Equity Securities [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	0	0	0	7
Trading Account Assets [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	76	35	137	849
Commercial Mortgage Loans [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	6,075	6,871	22,478	20,584
Policy Loans [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	176	273	515	625
Short-term Investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	77	140	255	503
Other Long-term Investments [Member]
Schedule of Investment Income, Reported Amounts, by Category [Line Items]
Gross investment income	$ 754	$ 6,614	$ 2,183	$ 7,529