Significant Accounting Policies - Additional Information (Detail) $ in Thousands		12 Months Ended
	Aug. 01, 2021 USD ($)	Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Jan. 01, 2021 USD ($)	Dec. 31, 2020 USD ($)
Significant of Account Policies [Line Items]
Number of reportable segments | segment		4
Mortgage loans		$ 279,199	$ 181,305
Concentration risk percentage		100.00%
Capital called from investment funds		$ 154,000
Investment funds, unfunded commitments		$ 744,000
Percentage of investment securities not classified as corporate securities, state and municipal securities, redeemable preferred stocks and U.S. government securities (less than)		1.00%
Fair value determined by third party		97.00%
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]		Accrued investment income
Agent debit balances		$ 501,000	460,000
Agent debit balances, allowance for credit losses		1,200
Advertising costs charged to earnings and included in other operating		19,200	9,400	$ 10,000
Capitalized advertising costs		1,600,000	1,500,000
Carrying value of investment in low-income housing interests		267,000	315,000
Obligations under future commitments for low-income housing interests		72,000
Original cost of property and equipment		455,000	406,000
Accumulated depreciation		215,000	194,000
Depreciation expense		21,000	21,000	20,000
Insurance policy charges		12,900	13,500	14,200
Equity		$ 4,486,803	3,949,577	2,003,808	$ 933,521	$ 8,771,092
Accounting Standards Update 2018-12
Significant of Account Policies [Line Items]
Equity					$ 26,500
Reinsurance recoverables			59,700	$ 82,400		$ 49,900
Equity Option | Torchmark Corporation 2018 Incentive Plan
Significant of Account Policies [Line Items]
Term over which monthly data points are used to derive volatility		3 years
Equity Option | Torchmark Corporation 2018 Incentive Plan | Employee | Three Year Vesting Period
Significant of Account Policies [Line Items]
Option grants contractual term		7 years
Vesting period		3 years
Equity Option | Torchmark Corporation 2018 Incentive Plan | Employee | Five Year Vesting Period
Significant of Account Policies [Line Items]
Option grants contractual term		10 years
Vesting period		5 years
Equity Option | Torchmark Corporation 2018 Incentive Plan | Director
Significant of Account Policies [Line Items]
Vesting period		6 months
Investment in Limited Partnerships
Significant of Account Policies [Line Items]
Capital called from investment funds		$ 154,000	$ 201,000
Investment funds, unfunded commitments		744,368
Commercial mortgage loan participations
Significant of Account Policies [Line Items]
Accrued interest receivable		$ 1,700
Minimum | Equipment and Software
Significant of Account Policies [Line Items]
Property and equipment, estimated useful life		3 years
Minimum | Building and Improvements
Significant of Account Policies [Line Items]
Property and equipment, estimated useful life		15 years
Minimum | Investment in Limited Partnerships
Significant of Account Policies [Line Items]
Investment funds ownership percentage		1.00%
Maximum | Equipment and Software
Significant of Account Policies [Line Items]
Property and equipment, estimated useful life		15 years
Maximum | Building and Improvements
Significant of Account Policies [Line Items]
Property and equipment, estimated useful life		40 years
Maximum | Investment in Limited Partnerships
Significant of Account Policies [Line Items]
Investment funds ownership percentage		20.00%
Commercial loan participations
Significant of Account Policies [Line Items]
Financing receivable, term		3 years
Financing receivable, extension term		2 years
Unfunded Loan Commitment
Significant of Account Policies [Line Items]
Mortgage loans		$ 25,000
Beazley Insurance Company
Significant of Account Policies [Line Items]
Acquisition consideration	$ 59,200
Life insurance
Significant of Account Policies [Line Items]
Proportion of future policy reserves which are not universal life type		92.00%
Low-income housing credits and certain limited partnerships | Total Assets | Investment Type
Significant of Account Policies [Line Items]
Concentration risk percentage		2.00%