Condensed Statements of Cash Flows (unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 45,585us-gaap_NetIncomeLoss	$ 36,159us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in net income attributable to AB Unitholders	(51,616)	(41,371)
Cash distributions received from AB	63,184us-gaap_ProceedsFromDividendsReceived	63,457us-gaap_ProceedsFromDividendsReceived
Changes in assets and liabilities:
Increase in other liabilities	6,034	5,215
Net cash provided by operating activities	63,187	63,460
Cash flows from investing activities:
Investments in AB from cash distributions paid to AB consolidated rabbi trust	0	(26)
Investments in AB with proceeds from exercise of compensatory options to buy AB Holding Units	(3,901)	(4,656)
Net cash used in investing activities	(3,901)	(4,682)
Cash flows from financing activities:
Cash distributions to Unitholders	(57,168)us-gaap_PaymentsOfOrdinaryDividends	(57,662)us-gaap_PaymentsOfOrdinaryDividends
Capital contributions to AB	(6,019)us-gaap_PaymentsOfCapitalDistribution	(5,772)us-gaap_PaymentsOfCapitalDistribution
Proceeds from exercise of compensatory options to buy AB Holding Units	3,901	4,656
Net cash used in financing activities	(59,286)	(58,778)
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

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