Changes in Capital (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Changes in capital [Roll Forward]
Partners' capital, beginning balance			$ 4,061,740
Partners' capital attributable to non-controlling interest, beginning balance			1,564
Partner's capital including portion attributable to non-controlling interest, beginning balance			4,063,304
Comprehensive income:
Net income	$ 181,926	$ 152,272	388,772	$ 308,527
Other comprehensive income, net of tax:
Foreign currency translation adjustments	(20,556)	7,489	(10,635)	16,356
Changes in employee benefit related items	293	267	463	456
Comprehensive income attributable to AB Unitholders	161,817	142,012	356,087	290,911
Distributions to General Partner and unitholders			(466,522)	(339,139)
Partners' capital, ending balance	3,972,899		3,972,899
Partners' capital attributable to non-controlling interest, ending balance	1,659		1,659
Partner's capital including portion attributable to non-controlling interest, ending balance	3,974,558		3,974,558
Partners’ Capital Attributable to AB Unitholders
Changes in capital [Roll Forward]
Partners' capital, beginning balance			4,061,740	4,032,017
Comprehensive income:
Net income			365,861	275,040
Other comprehensive income, net of tax:
Foreign currency translation adjustments			(10,611)	15,407
Changes in employee benefit related items			463	456
Other			374	8
Comprehensive income attributable to AB Unitholders			356,087	290,911
Distributions to General Partner and unitholders			(466,522)	(339,139)
Compensation-related transactions			(11,805)	(96,889)
Capital contributions to affiliates			(1,178)	(280)
Purchase of non-controlling interest				173
Distributions to non-controlling interests of our consolidated venture capital fund				0
Other				(679)
Partners' capital, ending balance	3,972,899	3,886,114	3,972,899	3,886,114
Non-Redeemable Non-Controlling Interests In Consolidated Entities
Changes in capital [Roll Forward]
Partners' capital attributable to non-controlling interest, beginning balance			1,564	36,172
Comprehensive income:
Net income attributable to noncontrolling interest			118	9,610
Other comprehensive income, net of tax:
Foreign currency translation adjustments			(23)	949
Changes in employee benefit related items			0	0
Other			0	0
Comprehensive income attributable to non-controlling interest			95	10,559
Distributions to General Partner and unitholders			0	0
Compensation-related transactions			0	0
Capital contributions to affiliates			0	0
Purchase of non-controlling interest				(2,006)
Distributions to non-controlling interests of our consolidated venture capital fund				(7,868)
Other				0
Partners' capital attributable to non-controlling interest, ending balance	1,659	36,857	1,659	36,857
Total Capital
Changes in capital [Roll Forward]
Partner's capital including portion attributable to non-controlling interest, beginning balance			4,063,304	4,068,189
Comprehensive income:
Net income			365,979	284,650
Other comprehensive income, net of tax:
Foreign currency translation adjustments			(10,634)	16,356
Changes in employee benefit related items			463	456
Other			374	8
Comprehensive income			356,182	301,470
Distributions to General Partner and unitholders			(466,522)	(339,139)
Compensation-related transactions			(11,805)	(96,889)
Capital contributions to affiliates			(1,178)	(280)
Purchase of non-controlling interest				(1,833)
Distributions to non-controlling interests of our consolidated venture capital fund				(7,868)
Other				(679)
Partner's capital including portion attributable to non-controlling interest, ending balance	3,974,558	$ 3,922,971	3,974,558	$ 3,922,971
Difference between Revenue Guidance in Effect before and after Topic 606 | ASC 606 and ASU 2016-01 | Partners’ Capital Attributable to AB Unitholders
Other comprehensive income, net of tax:
Impact of adoption of revenue recognition standard ASC 606 and ASU 2016-01	34,577		34,577
Difference between Revenue Guidance in Effect before and after Topic 606 | ASC 606 and ASU 2016-01 | Non-Redeemable Non-Controlling Interests In Consolidated Entities
Other comprehensive income, net of tax:
Impact of adoption of revenue recognition standard ASC 606 and ASU 2016-01	0		0
Difference between Revenue Guidance in Effect before and after Topic 606 | ASC 606 and ASU 2016-01 | Total Capital
Other comprehensive income, net of tax:
Impact of adoption of revenue recognition standard ASC 606 and ASU 2016-01	$ 34,577		$ 34,577