Note Receivable	6 Months Ended
Mar. 31, 2013
Receivables [Abstract]
Note Receivable	NOTE 2. *NOTE RECEIVABLE* As part of the proceeds from the sale of Unidym in January 2011, Arrowhead received a Note Receivable from Wisepower (the “Wisepower Note”) in the face amount of $2.5 million. On January 24, 2013, the Company entered into an agreement to sell the Wisepower Note. As consideration for selling the Wisepower Note the Company received 1,570,000 shares of Wisepower stock, (the “First Tranche”). Per the terms of the agreement, the Company was entitled to receive additional consideration (the “Second Tranche”) based on the proceeds realized from the First Tranche, at which time the Company would deliver the Wisepower Note to the Purchaser. During the three months ended March 31, 2013, the Company sold 1,170,000 shares of Wisepower from the First Tranche, and realized approximately $1.2 million in proceeds prior to a trading halt of Wisepower stock on March 22, 2013. As of May 6, 2013 the trading of Wisepower stock had not resumed. It is unclear whether trading will resume and whether the Company will receive any further proceeds from the sale of Wisepower stock, and whether the Company will receive the Second Tranche. Accordingly, the remaining 400,000 shares of Wisepower stock have been recorded at no value. The Company recorded the $1.2 million proceeds realized from sales of shares from the First Tranche against the $2.5 million value of the Wisepower Note, and has recorded a reserve for the balance of the Wisepower Note in the amount of approximately $1.3 million. The Company is pursuing its rights under the applicable agreements.

Note Receivable

6 Months Ended

Mar. 31, 2013

NOTE 2. NOTE RECEIVABLE

As part of the proceeds from the sale of Unidym in January 2011, Arrowhead received a Note Receivable from Wisepower (the “Wisepower Note”) in the face amount of $2.5 million. On January 24, 2013, the Company entered into an agreement to sell the Wisepower Note. As consideration for selling the Wisepower Note the Company received 1,570,000 shares of Wisepower stock, (the “First Tranche”). Per the terms of the agreement, the Company was entitled to receive additional consideration (the “Second Tranche”) based on the proceeds realized from the First Tranche, at which time the Company would deliver the Wisepower Note to the Purchaser.

During the three months ended March 31, 2013, the Company sold 1,170,000 shares of Wisepower from the First Tranche, and realized approximately $1.2 million in proceeds prior to a trading halt of Wisepower stock on March 22, 2013. As of May 6, 2013 the trading of Wisepower stock had not resumed. It is unclear whether trading will resume and whether the Company will receive any further proceeds from the sale of Wisepower stock, and whether the Company will receive the Second Tranche. Accordingly, the remaining 400,000 shares of Wisepower stock have been recorded at no value. The Company recorded the $1.2 million proceeds realized from sales of shares from the First Tranche against the $2.5 million value of the Wisepower Note, and has recorded a reserve for the balance of the Wisepower Note in the amount of approximately $1.3 million. The Company is pursuing its rights under the applicable agreements.