Fair value of contingent consideration obligation.

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- Definition

Percentage of reduction in workforce.

+ References

No definition available.

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- Definition

Proceeds from upfront payments and equity investments.

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No definition available.

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- Definition

Upfront payment.

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No definition available.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

+ References

No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

The cash inflow from the additional capital contribution to the entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Organization and Significant Accounting Policies - Additional Information (Detail) - USD ($)		3 Months Ended
	Nov. 18, 2016	Dec. 31, 2016	Dec. 31, 2015	Nov. 29, 2016	Sep. 30, 2016	Sep. 30, 2015
Schedule Of Investments [Line Items]
Percentage of workforce reduced due to discontinued clinical program				30.00%
Cash and cash equivalents		$ 102,105,569	$ 62,165,088		$ 85,366,448	$ 81,214,354
Net increase (decrease) in cash		16,739,121	$ (19,049,266)
Proceeds from the issuance of common stock		12,500,000
Restricted Cash		0			0
Investments		0			0
Fair value of contingent consideration obligation due to discontinuation of clinical trials		0			$ 0
Maximum
Schedule Of Investments [Line Items]
Amount insured in FDIC per account		$ 250,000
Property, Plant and Equipment, Useful Life		7 years
Minimum
Schedule Of Investments [Line Items]
Property, Plant and Equipment, Useful Life		3 years
Amgen
Schedule Of Investments [Line Items]
Proceeds from upfront payments and equity investments		$ 42,500,000
Amgen \| Common Stock Purchase Agreement
Schedule Of Investments [Line Items]
Proceeds from the issuance of common stock	$ 12,500,000
Amgen \| ARO-LPA Agreement
Schedule Of Investments [Line Items]
Common stock issued	1,745,810
Upfront payment	$ 30,000,000
Amgen \| ARO-LPA Agreement \| Common Stock Purchase Agreement
Schedule Of Investments [Line Items]
Common stock issued	1,745,810