Condensed Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net income	$ 81,087	$ 62,259
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in net income attributable to AB Unitholders	(88,907)	(69,914)
Cash distributions received from AB	106,091	91,562
Changes in assets and liabilities:
Decrease in other assets	92	0
Increase (decrease) in other liabilities	5,778	(901)
Net cash provided by operating activities	104,141	83,006
Cash flows from investing activities:
Investments in AB with proceeds from exercise of compensatory options to buy AB Holding Units	(1,914)	(147)
Net cash used in investing activities	(1,914)	(147)
Cash flows from financing activities:
Cash distributions to Unitholders	(98,045)	(83,705)
Capital contributions (to) from AB	(6,096)
Capital contributions (to) from AB		699
Proceeds from exercise of compensatory options to buy AB Holding Units	1,914	147
Net cash used in financing activities	(102,227)	(82,859)
Change in cash and cash equivalents	0	0
Cash and cash equivalents as of beginning of period	0	0
Cash and cash equivalents as of end of period	$ 0	$ 0