Equity (OTTI Net Unrealized Investment Gains (Losses) in AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 428,612
Ending Balance	1,533,059	$ 428,612
Accumulated Other Comprehensive Income (Loss) Related to Net Unrealized Investment Gains (Losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	429,546	(323,295)	$ (90,117)
Ending Balance	1,533,767	429,546	(323,295)
OTTI | Net Unrealized Gains (Losses) on Investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	14,309	(3,334)	12,311
Net unrealized investment gains (losses) on investments arising during the period		17,795	(15,199)
Reclassification adjustment for (gains) losses included in net income		(100)	(205)
Reclassification adjustment for OTTI losses excluded from net income(1)		(52)	(241)
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs		0	0
Impact of net unrealized investment (gains) losses on future policy benefits and other liabilities		0	0
Reclassification due to implementation of ASU 2016-13	(14,309)
Ending Balance	0	14,309	(3,334)
OTTI | Deferred Policy Acquisition Costs and Other Costs
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(1,199)	(1,119)	(1,008)
Net unrealized investment gains (losses) on investments arising during the period		0	0
Reclassification adjustment for (gains) losses included in net income		0	0
Reclassification adjustment for OTTI losses excluded from net income(1)		0	0
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs		(80)	(111)
Impact of net unrealized investment (gains) losses on future policy benefits and other liabilities		0	0
Reclassification due to implementation of ASU 2016-13	1,199
Ending Balance	0	(1,199)	(1,119)
OTTI | Future Policy Benefits and Other Liabilities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(119)	(68)	(157)
Net unrealized investment gains (losses) on investments arising during the period		0	0
Reclassification adjustment for (gains) losses included in net income		0	0
Reclassification adjustment for OTTI losses excluded from net income(1)		0	0
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs		0	0
Impact of net unrealized investment (gains) losses on future policy benefits and other liabilities		(51)	89
Reclassification due to implementation of ASU 2016-13	119
Ending Balance	0	(119)	(68)
OTTI | Deferred Income Tax (Liability) Benefit
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(3,654)	27	(3,263)
Net unrealized investment gains (losses) on investments arising during the period		(3,741)	3,192
Reclassification adjustment for (gains) losses included in net income		21	43
Reclassification adjustment for OTTI losses excluded from net income(1)		11	51
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs		17	23
Impact of net unrealized investment (gains) losses on future policy benefits and other liabilities		11	(19)
Reclassification due to implementation of ASU 2016-13	3,654
Ending Balance	0	(3,654)	27
OTTI | Accumulated Other Comprehensive Income (Loss) Related to Net Unrealized Investment Gains (Losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	9,337	(4,494)	7,883
Net unrealized investment gains (losses) on investments arising during the period		14,054	(12,007)
Reclassification adjustment for (gains) losses included in net income		(79)	(162)
Reclassification adjustment for OTTI losses excluded from net income(1)		(41)	(190)
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs and other costs		(63)	(88)
Impact of net unrealized investment (gains) losses on future policy benefits and other liabilities		(40)	70
Reclassification due to implementation of ASU 2016-13	(9,337)
Ending Balance	$ 0	$ 9,337	$ (4,494)