Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended																12 Months Ended
		Dec. 31, 2016		Sep. 30, 2016		Jun. 30, 2016	[1]	Mar. 31, 2016	[1]	Dec. 31, 2015	[1]	Sep. 30, 2015	[1]	Jun. 30, 2015	[1]	Mar. 31, 2015	[1]	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Data [Abstract]
Equity in net income attributable to AB Unitholders		$ 78,630		$ 55,925		$ 44,657		$ 60,177		$ 56,890		$ 48,387		$ 53,799		$ 51,008		$ 239,389	$ 210,084	$ 200,931
Net income		$ 72,664		$ 50,258		$ 39,072		$ 54,592		$ 51,087		$ 42,086		$ 47,614		$ 44,977		$ 216,586	$ 185,764	$ 178,468
Basic net income per unit (in dollars per unit)		$ 0.77	[1],[2]	$ 0.52	[1],[2]	$ 0.40	[2]	$ 0.55	[2]	$ 0.53	[2]	$ 0.42	[2]	$ 0.47	[2]	$ 0.45	[2]	$ 2.24	$ 1.87	$ 1.84
Diluted net income per unit (in dollars per unit)		0.77	[1],[2]	0.52	[1],[2]	0.40	[2]	0.55	[2]	0.52	[2]	0.42	[2]	0.47	[2]	0.45	[2]	$ 2.23	$ 1.86	$ 1.84
Cash distributions per unit (in dollars per share)	[3],[4]	$ 0.67		$ 0.45		$ 0.40		$ 0.40		$ 0.50		$ 0.43		$ 0.48		$ 0.45

[1] Certain prior-period amounts have been revised, see Note 2 for a discussion of the revision.

[2] Basic and diluted net income per unit are computed independently for each of the periods presented. Accordingly, the sum of the quarterly net income per unit amounts may not agree to the total for the year.

[3] Cash distributions reflect the impact of AB’s non-GAAP adjustments.

[4] Declared and paid during the following quarter.