Condensed Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Equity in net income attributable to AB Unitholders	$ 59,023	$ 65,388	$ 111,661	$ 131,086
Income taxes	6,749	6,931	12,948	14,469
Net income	$ 52,274	$ 58,457	$ 98,713	$ 116,617
Net income per unit:
Basic (in dollars per unit)	$ 0.54	$ 0.59	$ 1.03	$ 1.19
Diluted (in dollars per unit)	$ 0.54	$ 0.59	$ 1.03	$ 1.19