Equity (Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024		Jun. 30, 2025	Jun. 30, 2024
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Begining Balance				$ 4,701,980
Income tax benefit (expense)	$ (70,868)	$ 14,270	[1]	(159,810)	$ 123,549	[1]
Ending Balance	5,681,715			5,681,715
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Begining Balance				(21,941)	(18,085)
Change in OCI before reclassifications				4,724	(4,178)
Amounts reclassified from AOCI				0	0
Income tax benefit (expense)				(1,293)	275
Ending Balance	(18,510)	(21,988)		(18,510)	(21,988)
Net unrealized investment gains (losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Begining Balance				(1,192,702)	(927,778)
Change in OCI before reclassifications				536,382	(448,732)
Amounts reclassified from AOCI				66,846	(20,268)
Income tax benefit (expense)				(126,514)	98,567
Ending Balance	(715,988)	(1,298,211)		(715,988)	(1,298,211)
Interest Rate Remeasurement of Future Policy Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Begining Balance				117,558	71,195
Change in OCI before reclassifications				(15,931)	66,215
Amounts reclassified from AOCI				0	0
Income tax benefit (expense)				3,345	(13,905)
Ending Balance	104,972	123,505		104,972	123,505
Gain (Loss) from Changes in Non-Performance Risk on Market Risk Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Begining Balance				495,208	843,707
Change in OCI before reclassifications				168,322	(183,872)
Amounts reclassified from AOCI				0	0
Income tax benefit (expense)				(35,348)	38,612
Ending Balance	628,182	698,447		628,182	698,447
Accumulated Other Comprehensive   Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Begining Balance	(268,909)	(443,442)		(601,877)	(30,961)
Change in OCI before reclassifications				693,497	(570,567)
Amounts reclassified from AOCI				66,846	(20,268)
Income tax benefit (expense)				(159,810)	123,549
Ending Balance	(1,344)	(498,247)	[2]	(1,344)	(498,247)	[2]
Cash flow hedges | Net unrealized investment gains (losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Begining Balance				111,000	12,000
Ending Balance	$ (167,000)	$ 75,000		$ (167,000)	$ 75,000

[1] Amounts reflect revision to prior period Financial Statements. See Note 17 for additional information.

[2] Amounts reflect revision to prior period Financial Statements. See Note 17 for additional information.