The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Sep. 30, 2014
Finite Lived Intangible Assets [Line Items]
Amortization expense	$ 155,366us-gaap_AmortizationOfIntangibleAssets	$ 13,663us-gaap_AmortizationOfIntangibleAssets	$ 169,030us-gaap_AmortizationOfIntangibleAssets	$ 27,327us-gaap_AmortizationOfIntangibleAssets	$ 54,653us-gaap_AmortizationOfIntangibleAssets
Amortization of license agreements remainder of fiscal year 2015	877,541		877,541
Amortization of license agreements in 2016	1,714,313		1,714,313
Amortization of license agreements in 2017	1,700,429		1,700,429
Amortization of license agreements in 2018	1,700,429		1,700,429
Amortization of license agreements in 2019	1,700,429		1,700,429
Amortization of license agreements in 2020	1,700,429		1,700,429
Amortization of license agreements, thereafter	15,363,152		15,363,152
Novartis RNAi [Member] \| Licensing Agreements
Finite Lived Intangible Assets [Line Items]
Amortization period of intangible assets			21 years
Finite-lived intangible assets, accumulated amortization	12,367		12,367
Novartis RNAi [Member] \| Patents [Member]
Finite Lived Intangible Assets [Line Items]
Amortization period of intangible assets			14 years
Finite-lived intangible assets, accumulated amortization	129,335		129,335
Roche Madison [Member] \| Licensing Agreements
Finite Lived Intangible Assets [Line Items]
Amortization period of intangible assets			4 years
Finite-lived intangible assets, accumulated amortization	$ 188,790		$ 188,790