Schedule II - Aflac Incorporated (Parent Only) - Condensed Balance Sheet (Detail 1) - USD ($) $ in Millions		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investments and cash:
Available for sale, fixed maturity securities		$ 75,741	$ 98,696
Other investments		4,070	3,842
Cash and cash equivalents		3,943	5,051
Total investments and cash		117,397	142,978
Other assets		3,105	3,092
Assets		131,017	157,542
Liabilities:
Notes payable		7,295	7,839
Other Liabilities		4,847	4,760
Total liabilities		108,652	124,289
Shareholders' equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2022 and 2021; issued 1,354,079 shares in 2022 and 1,352,739 shares in 2021		135	135
Additional paid-in capital		2,641	2,529
Retained earnings		44,568	41,381
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains (losses)		(3,640)	(2,013)
Unrealized gains (losses) on fixed maturity securities		(702)	9,602
Unrealized gains (losses) on derivatives		(27)	(30)
Pension liability adjustment		(36)	(166)
Treasury stock, at average cost		(20,574)	(18,185)
Total shareholders' equity		22,365	33,253	$ 33,559	$ 28,959
Total liabilities and shareholders' equity		131,017	157,542
Parent Company
Investments and cash:
Available for sale, fixed maturity securities		1,744	1,828
Investments in subsidiaries	[1]	25,197	35,905
Other investments		1,461	1,413
Cash and cash equivalents		1,143	2,097	$ 2,126	$ 2,508
Total investments and cash		29,545	41,243
Due from subsidiaries	[1]	267	248
Other assets		964	640
Assets		30,776	42,131
Liabilities:
Employee benefit plans		291	336
Notes payable		7,069	7,579
Other Liabilities		1,051	963
Total liabilities		8,411	8,878
Shareholders' equity:
Common stock of $.10 par value. In thousands: authorized 1,900,000 shares in 2022 and 2021; issued 1,354,079 shares in 2022 and 1,352,739 shares in 2021		135	135
Additional paid-in capital		2,641	2,529
Retained earnings		44,568	41,381
Accumulated other comprehensive income (loss):
Unrealized foreign currency translation gains (losses)		(3,640)	(2,013)
Unrealized gains (losses) on fixed maturity securities		(702)	9,602
Unrealized gains (losses) on derivatives		(27)	(30)
Pension liability adjustment		(36)	(166)
Treasury stock, at average cost		(20,574)	(18,185)
Total shareholders' equity		22,365	33,253
Total liabilities and shareholders' equity		$ 30,776	$ 42,131

[1] Eliminated in consolidation