Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Operating activities
Net income (loss)	$ 342,645	$ (155,891)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Interest sensitive and index product benefits	304,220	57,911
Amortization of deferred sales inducements	54,214	46,601	$ 192,252
Annuity product charges	(95,613)	(62,591)
Change in fair value of embedded derivatives	162,202	404,440
Change in traditional life and accident and health insurance reserves	(9,563)	1,720
Policy acquisition costs deferred	(191,814)	(66,767)
Amortization of deferred policy acquisition costs	77,337	68,235	279,700
Provision for depreciation and other amortization	3,350	3,025
Amortization of discounts and premiums on investments	2,601	13,450
Realized gains/losses on investments	94,050	27,787
Distributions from equity method investments	24,601	0
Change in fair value of derivatives	(409,767)	(45,890)
Deferred income taxes	93,247	(40,895)
Share-based compensation	1,946	9,904
Change in accrued investment income	28,227	426
Change in income taxes recoverable/payable	13,512	4,677
Change in other assets	(11,255)	(34,940)
Change in other policy funds and contract claims	(7,645)	(207,895)
Change in market risk benefits, net	(138,771)	192,253
Change in collateral held for derivatives	390,978	184,088
Change in funds withheld from reinsurers	256,921	342,602
Change in other liabilities	58,489	145,648
Other	25,894	(22,855)
Net cash provided by operating activities	1,070,006	865,043
Sales, maturities, or repayments of investments:
Fixed maturity securities, available for sale	4,707,376	3,150,639
Mortgage loans on real estate	442,126	279,348
Derivative instruments	303,371	(132)
Other investments	1,103,923	705,059
Acquisitions of investments:
Fixed maturity securities, available for sale	(2,323,893)	(2,039,525)
Mortgage loans on real estate	(191,028)	(534,632)
Real estate investments acquired	(35,649)	(120,907)
Derivative instruments	(203,551)	(205,561)
Other investments	(459,826)	(425,596)
Purchases of property, furniture and equipment	(4,631)	(4,192)
Net cash provided by investing activities	3,338,218	804,501
Financing activities
Receipts credited to annuity policyholder account balances	2,348,431	1,370,663
Coinsurance deposits	(91,042)	(215,927)
Return of annuity policyholder account balances	(2,910,342)	(1,601,547)
Repayment of loan payable	(1,875)	(1,875)
Acquisition of treasury stock	0	(293,193)
Proceeds from issuance of common stock, net	264	(3,631)
Change in checks in excess of cash balance	(19,480)	(54,932)
Dividends paid on preferred stock	(10,919)	(10,919)
Net cash used in financing activities	(684,963)	(811,361)
Increase in cash and cash equivalents	3,723,261	858,183
Cash and cash equivalents at beginning of period	9,772,586	1,919,669	1,919,669
Cash and cash equivalents at end of period	13,495,847	2,777,852	9,772,586
Cash paid during period for:
Interest expense	6,358	5,803
Income taxes	546	262,020
Income tax refunds received	14,059	52,500
Non-cash operating activity:
Deferral of sales inducements	$ 127,704	$ 45,267	$ 513,793