v2.4.0.8

Income Taxes - Reconciliation of the Federal Statutory Rate to the Effective Income Tax Rate (Detail)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
Federal statutory rate	(34.00%)	(34.00%)	(34.00%)
Increase in deferred income tax asset valuation allowance	38.00%	37.00%	31.00%
State income taxes, net of federal effect	(6.00%)	(5.00%)	(5.00%)
Research and development credits	0.00%	3.00%	1.00%
Expired net operating loss and other credits	0.00%	0.00%	6.00%
Other	2.00%	(1.00%)	1.00%
Effective income tax rate	0.00%	0.00%	0.00%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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AVANIR PHARMACEUTICALS, INC. 10-K