Pre tax compensation expense.

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- Definition

Share based compensation arrangement by share based payment award options grants in period fair value.

+ References

No definition available.

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- Definition

Weighted average period to recognize pre-tax compensation expense.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-Paragraph A240

-Subparagraph a

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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Stock-Based Compensation - Additional Information (Detail) (USD $)	9 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Sep. 30, 2012	Sep. 30, 2011
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance	6,055,535
Options granted and outstanding to purchase	2,859,794		1,910,794	729,096
Options granted outside of Equity Incentive plans	251,200
Options granted	949,000		1,229,500
Stock-based compensation expense	$ 1,114,375	$ 837,188
Fair value of the options granted	1,197,588	3,505,912
Intrinsic value of the options exercised	0
Stock options exercised	0		4,883
Dividend yield	0.00%
Calando Pharmaceuticals, Inc.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of the options granted	0	33,690
Pre-tax compensation expense	39,169
Weighted average period to recognize pre-tax compensation expense	2 years 2 months 12 days
Arrowhead
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Pre-tax compensation expense	$ 3,775,514
Weighted average period to recognize pre-tax compensation expense	2 years 10 months 24 days
2000 Stock Option Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance	153,200
Options granted and outstanding to purchase	152,900
2004 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance	2,965,860
Options granted and outstanding to purchase	2,455,694
Shares authorized for issuance	3,000,000
Shares available for issuance	510,166
Options granted	949,000