Reinsurance (Reinsurance amounts included in the Statements of Financial Position) (Details) - USD ($) $ in Thousands		Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024	Dec. 31, 2023
Effects of Reinsurance [Line Items]
Reinsurance recoverables and deposit receivables		$ 50,219,999	$ 48,247,817
Policy loans		(1,613,609)	(1,541,480)
Deferred policy acquisition costs		(8,203,410)	(7,807,060)	$ (7,551,362)	$ (7,144,736)
Deferred sales inducements		(308,974)	(322,351)
Market risk benefit assets		2,534,340	2,637,363	2,550,164
Other assets		1,816,473	1,850,800
Future policy benefits		26,057,472	25,113,767	23,030,579
Market risk benefit liabilities		4,668,492	4,281,244	$ 4,370,960
Other liabilities	[1]	4,038,981	4,199,803
Impacts of Reinsurance
Effects of Reinsurance [Line Items]
Reinsurance recoverables and deposit receivables		50,219,999	48,247,817
Policy loans		(1,151,763)	(1,143,726)
Deferred policy acquisition costs		(3,258,052)	(3,319,067)
Deferred sales inducements		(31,238)	(32,573)
Market risk benefit assets		1,265,373	1,145,580
Other assets		1,486,243	1,538,231
Policyholders’ account balances		5,358,823	5,567,661
Future policy benefits		7,709,251	7,443,997
Market risk benefit liabilities		247,271	302,310
Reinsurance and funds withheld payables		9,042,306	8,611,141
Other liabilities		3,213,391	3,282,713
Unaffiliated activity
Effects of Reinsurance [Line Items]
Market risk benefit assets		894,563	804,015
Other assets		1,085,632	1,118,974
Policyholders’ account balances		1,600,235	1,665,998
Future policy benefits		150	160
Market risk benefit liabilities		118,372	151,432
Reinsurance and funds withheld payables		3,300,174	3,360,901
Other liabilities		243,574	257,929
Unaffiliated activity
Effects of Reinsurance [Line Items]
Policy loans		(49,378)	(48,644)
Deferred policy acquisition costs		$ (634,600)	$ (637,555)

[1] See Note 4 for details of balances associated with variable interest entities.