Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 1,193,485	$ 788,619	$ 775,457
Other comprehensive income (loss):
Foreign currency translation adjustments, before reclassification and tax	(20,843)	14,262	(47,208)
Less: reclassification adjustment for (losses) included in net income upon liquidation	(10,197)	(389)	0
Foreign currency translation adjustments, before tax	(10,646)	14,651	(47,208)
Income tax benefit (expense)	59	(618)	1,215
Foreign currency translation adjustments, net of tax	(10,587)	14,033	(45,993)
Changes in employee benefit related items:
Amortization of prior service cost	24	24	24
Recognized actuarial gain	1,504	9,135	6,922
Less: reclassification adjustment for (losses) included in net income upon retirement plan liquidation	(4,931)	0	0
Changes in employee benefit related items	6,459	9,159	6,946
Income tax (expense)	(89)	(79)	(95)
Employee benefit related items, net of tax	6,370	9,080	6,851
Other comprehensive (loss) gain	(4,217)	23,113	(39,142)
Less: Comprehensive income (loss) in consolidated entities attributable to non-controlling interests	20,238	24,009	(56,356)
Comprehensive income attributable to AB Unitholders	$ 1,169,030	$ 787,723	$ 792,671