Investments (Cumulative Noncredit Portion of Other Than Temporary Impairment Recognized in Other Comprehensive Income and Change in Fair Value Since Other Than Temporary Impairment) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Investment Holdings [Line Items]
Amortized cost	$ 597,409	$ 679,265
OTTI recognized in other comprehensive income	(174,271)	(176,334)
Change in fair value since OTTI was recognized	217,222	216,081
Fair value	640,360	719,012
Fixed Maturity Securities [Member] | Corporate Securities [Member]
Investment Holdings [Line Items]
Amortized cost	0	0
OTTI recognized in other comprehensive income	0	0
Change in fair value since OTTI was recognized	25	20
Fair value	25	20
Fixed Maturity Securities [Member] | Residential Mortgage Backed Securities [Member]
Investment Holdings [Line Items]
Amortized cost	597,409	679,265
OTTI recognized in other comprehensive income	(174,271)	(176,334)
Change in fair value since OTTI was recognized	217,197	216,061
Fair value	$ 640,335	$ 718,992