Net Income per Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Unit [Abstract]
General partnership interest in Company (percent)	1.00%		1.00%
Limited Partners interest in Company (as a percent)			99.00%
Net income per unit, basic and diluted [Abstract]
Net income attributable to AB Unitholders	$ 140,954	$ 158,035	$ 415,994	$ 448,820
Weighted average units outstanding – basic (in units)	265,585,000	268,133,000	267,448,000	269,896,000
Dilutive effect of compensatory options to buy AB Holding Units (in units)	400,000	590,000	455,000	554,000
Weighted average units outstanding – diluted (in units)	265,985,000	268,723,000	267,903,000	270,450,000
Basic net income per AB Unit (in dollars per unit)	$ 0.53	$ 0.58	$ 1.54	$ 1.65
Diluted net income per AB Unit (in dollars per unit)	$ 0.52	$ 0.58	$ 1.54	$ 1.64
Options excluded from diluted net income per unit computation due to their anti-dilutive effect (in units)	2,427,527	2,873,106	2,427,527	2,873,106