Income Taxes - Summary of Income Taxes (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Computation of equity in net income attributable to AB Unitholders [Abstract]
Net income attributable to AB Unitholders									$ 586,602,000	$ 570,383,000	$ 517,676,000
Multiplied by: weighted average equity ownership interest									36.20%	35.60%	35.90%
Equity in net income attributable to AB Unitholders	$ 57,485,000	$ 48,988,000	$ 54,409,000	$ 51,616,000	$ 63,563,000	$ 49,876,000	$ 48,467,000	$ 41,371,000	$ 212,498,000	$ 203,277,000	$ 185,912,000
Computation of income tax [Abstract]
AB qualifying revenues									$ 2,214,077,000	$ 2,153,317,000	$ 2,041,642,000
Multiplied by: weighted average equity ownership interest for calculating tax									30.80%	29.40%	27.90%
Multiplied by: federal tax									3.50%	3.50%	3.50%
Federal tax on partnership gross business income									$ 23,845,000	$ 22,131,000	$ 19,944,000
State income taxes									475,000	332,000	466,000
Income taxes									24,320,000	$ 22,463,000	$ 20,410,000
Changes in components for calculation of income tax [Abstract]
Increase in net income attributable to AB Unitholders (percent)										2.80%	10.20%
Increase in equity in net income attributable to AB Unitholders (percent)										4.50%	9.30%
Increase (decrease) in AB qualifying revenue (percent)										2.80%	5.50%
Increase (decrease) in income taxes (percent)										8.30%	10.10%
Unrecognized tax benefits	$ 0				$ 0				$ 0	$ 0