Condensed Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Equity in net income attributable to AB Unitholders	$ 63,201	$ 59,023	$ 133,115	$ 111,661
Income taxes	6,275	6,749	13,930	12,948
Net income	$ 56,926	$ 52,274	$ 119,185	$ 98,713
Net income per unit:
Basic (in dollars per unit)	$ 0.59	$ 0.54	$ 1.23	$ 1.03
Diluted (in dollars per unit)	$ 0.59	$ 0.54	$ 1.23	$ 1.03