Changes in Capital (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Changes in capital [Roll Forward]
Partners' capital, beginning balance	$ 4,032,017
Partners' capital attributable to non-controlling interest, beginning balance	36,172
Partner's capital including portion attributable to non-controlling interest, beginning balance	4,068,189
Comprehensive income:
Net income	156,255	$ 160,536
Other comprehensive income, net of tax:
Foreign currency translation adjustments	8,867	5,225
Changes in employee benefit related items	189	(433)
Comprehensive income attributable to AB Unitholders	148,899	171,019
Distributions to General Partner and unitholders	(198,040)	(153,433)
Capital contributions (to) from affiliates	(81)	6,348
Partners' capital, ending balance	3,964,122
Partners' capital attributable to non-controlling interest, ending balance	34,743
Partner's capital including portion attributable to non-controlling interest, ending balance	3,998,865
Partners’ Capital Attributable to AB Unitholders
Changes in capital [Roll Forward]
Partners' capital, beginning balance	4,032,017	3,992,748
Comprehensive income:
Net income	139,937	166,284
Other comprehensive income, net of tax:
Unrealized gains (losses) on investments	(18)	(6)
Foreign currency translation adjustments	8,791	5,174
Changes in employee benefit related items	189	(433)
Comprehensive income attributable to AB Unitholders	148,899	171,019
Distributions to General Partner and unitholders	(198,040)	(153,433)
Compensation-related transactions	(18,673)	(37,353)
Capital contributions (to) from affiliates	(81)	6,348
Other		(1)
Distributions to non-controlling interests of our consolidated venture capital fund	0
Partners' capital, ending balance	3,964,122	3,979,328
Non-Controlling Interests In Consolidated Entities
Changes in capital [Roll Forward]
Partners' capital attributable to non-controlling interest, beginning balance	36,172	24,473
Comprehensive income:
Net income attributable to noncontrolling interest	1,632	(6,902)
Other comprehensive income, net of tax:
Unrealized gains (losses) on investments	0	0
Foreign currency translation adjustments	76	51
Changes in employee benefit related items	0	0
Comprehensive income attributable to non-controlling interest	1,708	(6,851)
Distributions to General Partner and unitholders	0	0
Compensation-related transactions	0	0
Capital contributions (to) from affiliates	0	0
Other		0
Distributions to non-controlling interests of our consolidated venture capital fund	(3,137)
Partners' capital attributable to non-controlling interest, ending balance	34,743	17,622
Total Capital
Changes in capital [Roll Forward]
Partner's capital including portion attributable to non-controlling interest, beginning balance	4,068,189	4,017,221
Comprehensive income:
Net income	141,569	159,382
Other comprehensive income, net of tax:
Unrealized gains (losses) on investments	(18)	(6)
Foreign currency translation adjustments	8,867	5,225
Changes in employee benefit related items	189	(433)
Comprehensive income	150,607	164,168
Distributions to General Partner and unitholders	(198,040)	(153,433)
Compensation-related transactions	(18,673)	(37,353)
Capital contributions (to) from affiliates	(81)	6,348
Other		(1)
Distributions to non-controlling interests of our consolidated venture capital fund	(3,137)
Partner's capital including portion attributable to non-controlling interest, ending balance	$ 3,998,865	3,996,950
Adjustment
Other comprehensive income, net of tax:
Partners' capital, ending balance		$ (40,300)