Consolidated Statements of Changes in Partners' Capital - USD ($) $ in Thousands	Total	Receivables from Affiliates	AB Holding Units held for Long-term Incentive Compensation Plans	Accumulated Other Comprehensive Income (Loss)	Total Partners' Capital attributable to AB Unitholders	Non-redeemable Non-controlling Interests in Consolidated Entities	General Partner’s Capital	Limited Partners' Capital
Balance, beginning of year at Dec. 31, 2015		$ (14,498)	$ (29,332)	$ (95,353)		$ 24,473	$ 40,498	$ 4,091,433
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 694,846						6,733	666,625
Cash distributions							(5,384)	(532,180)
Long-term incentive compensation plans activity							58	5,802
(Retirement) issuance of AB Units, net			80,515				(805)	(80,084)
Other				0			0	3,214
Capital contributions from General Partner		1,200
Compensation plan accrual		313
Capital contributions from AB Holding		155
Purchases of AB Holding Units to fund long-term compensation plans, net			(235,893)
Long-term incentive compensation awards expense			152,012
Re-valuation of AB Holding Units held in rabbi trust			(269)
Unrealized gain (loss) on investments, net of tax				9
Foreign currency translation adjustment	(19,843)			(19,780)		(63)
Purchase of non-controlling interest						0
Changes in employee benefit related items, net of tax	(2,972)			(2,972)
Net income	21,488					11,398
Distributions (to) from non-controlling interests of our consolidated venture capital fund activities						364
Balance, end of year at Dec. 31, 2016	4,068,189	(12,830)	(32,967)	(118,096)	$ 4,032,017	36,172	41,100	4,154,810
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	720,800						6,624	655,779
Cash distributions							(6,449)	(637,690)
Long-term incentive compensation plans activity							211	20,859
(Retirement) issuance of AB Units, net			26,603				(266)	(27,339)
Other				0			1	2,422
Capital contributions from General Partner		344
Compensation plan accrual		156
Capital contributions from AB Holding		836
Purchases of AB Holding Units to fund long-term compensation plans, net			(219,627)
Long-term incentive compensation awards expense			185,234
Re-valuation of AB Holding Units held in rabbi trust			(1,931)
Unrealized gain (loss) on investments, net of tax				9
Foreign currency translation adjustment	28,123			27,140		983
Purchase of non-controlling interest						(2,006)
Changes in employee benefit related items, net of tax	(3,193)			(3,193)
Net income	58,397					9,632
Distributions (to) from non-controlling interests of our consolidated venture capital fund activities						(43,217)
Balance, end of year at Dec. 31, 2017	4,063,304	(11,494)	(42,688)	(94,140)	4,061,740	1,564	41,221	4,168,841
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	779,498						7,576	750,012
Cash distributions							(8,608)	(849,585)
Long-term incentive compensation plans activity							(39)	(3,880)
(Retirement) issuance of AB Units, net			25,589				(256)	(25,486)
Other				374			(3)	803
Capital contributions from General Partner		19
Compensation plan accrual		352
Capital contributions from AB Holding		(307)
Purchases of AB Holding Units to fund long-term compensation plans, net			(267,427)
Long-term incentive compensation awards expense			187,514
Re-valuation of AB Holding Units held in rabbi trust			19,022
Unrealized gain (loss) on investments, net of tax				0
Foreign currency translation adjustment	(18,617)			(18,571)		(46)
Purchase of non-controlling interest						0
Changes in employee benefit related items, net of tax	1,471			1,471
Net income	21,910					69
Distributions (to) from non-controlling interests of our consolidated venture capital fund activities						(638)
Balance, end of year at Dec. 31, 2018	$ 3,916,209	$ (11,430)	$ (77,990)	$ (110,866)	$ 3,915,260	$ 949	$ 40,240	$ 4,075,306