Condensed Statement of Changes in Partners' Capital - USD ($) $ in Thousands	Total	AB Holding Units held by AB to fund long-term incentive compensation plans	Accumulated Other Comprehensive (Loss) Income	General Partner	Limited Partner
Balance, beginning of period at Dec. 31, 2019		$ (27,436)	$ (40,628)	$ 1,402	$ 1,619,200
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 62,259			62	62,197
Cash distributions to Unitholders				(84)	(83,621)
Retirement of AB Holding Units					(14,220)
Issuance of AB Holding Units to fund long-term incentive compensation plan awards					8,458
Exercise of compensatory options to buy AB Holding Units					147
Change in AB Holding Units held by AB to fund long-term incentive compensation plans		(1,566)
Foreign currency translation adjustment, net of tax			(7,621)
Changes in employee benefit related items, net of tax			144
Balance, end of period at Mar. 31, 2020	1,516,434	(29,002)	(48,105)	1,380	1,592,161
Balance, beginning of period at Dec. 31, 2020	1,604,157	(20,171)	(33,898)	1,410	1,656,816
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	81,087			83	81,004
Cash distributions to Unitholders				(98)	(97,947)
Retirement of AB Holding Units					(29,847)
Issuance of AB Holding Units to fund long-term incentive compensation plan awards	100,861				100,861
Exercise of compensatory options to buy AB Holding Units					1,914
Change in AB Holding Units held by AB to fund long-term incentive compensation plans		(31,802)
Foreign currency translation adjustment, net of tax			(2,762)
Changes in employee benefit related items, net of tax			(274)
Balance, end of period at Mar. 31, 2021	$ 1,625,289	$ (51,973)	$ (36,934)	$ 1,395	$ 1,712,801