Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Federal tax on partnership gross income (in hundredths)	3.50%
Income tax computation rate on ownership interest (in hundredths)	3.50%
Holding's effective tax expense [Abstract]
UBT statutory rate	$ (2,623)	$ 6,489	$ 7,701
Federal tax on partnership gross business income	27,687	28,059	25,324
Credit for UBT paid by AllianceBernstein	2,623	(6,489)	(7,701)
Income tax expense	$ 27,687	$ 28,059	$ 25,324
UBT statutory rate (in hundredths)	4.00%	4.00%	4.00%
Federal tax on partnership gross business income (in hundredths)	(42.20%)	17.30%	13.20%
Credit for UBT paid by AllianceBernstein (in hundredths)	(4.00%)	(4.00%)	(4.00%)
Income tax effective tax rate (in hundredths)	(42.20%)	17.30%	13.20%

The amount of UBT tax credit received by entity from payments made by its limited partnership interest.

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Effective rate for tax credits generated by payments made by entity's limited partnership interest.

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The effective tax rate based on the (gross) business income.

+ References

No definition available.

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Income tax rate attributable to investment interests in limited partnerships owned by the entity.

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- Definition

The amount of tax based on New York City Unincorporated Business Tax (UBT).

+ References

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Tax rate attributable to operating income for unincorporated business entities operating in New York City, before credits paid for unincorporated business entities by a subsidiary.

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- Definition

The component of income tax expense for the period representing amounts paid or payable (or refundable) as determined by applying the provisions of enacted federal tax law to the domestic taxable Income or Loss from continuing operations.

+ References

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-Glossary Current Tax Expense (or Benefit)

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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