Investments (All Other Net Unrealized Investment Gains and Losses in AOCI) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	$ 64,805
Balance	241,016
Other Net Unrealized Investment Gains and Losses | Net Unrealized Gains (Losses) on Investments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	111,837
Net investment gains (losses) on investments arising during the period	341,126
Reclassification adjustment for (gains) losses included in net income	(72,361)
Reclassification adjustment for OTTI losses excluded from net income	512
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs	0
Impact of net unrealized investment (gains) losses on future policy benefits and policyholders’ account balances	0
Balance	381,114
Other Net Unrealized Investment Gains and Losses | Deferred Policy Acquisition Costs and Other Costs
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	(19,252)
Net investment gains (losses) on investments arising during the period	0
Reclassification adjustment for (gains) losses included in net income	0
Reclassification adjustment for OTTI losses excluded from net income	0
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs	(68,802)
Impact of net unrealized investment (gains) losses on future policy benefits and policyholders’ account balances	0
Balance	(88,054)
Other Net Unrealized Investment Gains and Losses | Future Policy Benefits and Policyholders’ Account Balances
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	2,647
Net investment gains (losses) on investments arising during the period	0
Reclassification adjustment for (gains) losses included in net income	0
Reclassification adjustment for OTTI losses excluded from net income	0
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs	0
Impact of net unrealized investment (gains) losses on future policy benefits and policyholders’ account balances	71,323
Balance	73,970
Other Net Unrealized Investment Gains and Losses | Deferred Income Tax (Liability) Benefit
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	(33,223)
Net investment gains (losses) on investments arising during the period	(119,393)
Reclassification adjustment for (gains) losses included in net income	25,326
Reclassification adjustment for OTTI losses excluded from net income	(179)
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs	24,081
Impact of net unrealized investment (gains) losses on future policy benefits and policyholders’ account balances	(24,963)
Balance	(128,351)
Other Net Unrealized Investment Gains and Losses | Total net unrealized investment gains (losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	62,009
Net investment gains (losses) on investments arising during the period	221,733
Reclassification adjustment for (gains) losses included in net income	(47,035)
Reclassification adjustment for OTTI losses excluded from net income	333
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs	(44,721)
Impact of net unrealized investment (gains) losses on future policy benefits and policyholders’ account balances	46,360
Balance	$ 238,679