Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Pay vs Performance Disclosure
Net loss attributable to Arrowhead Pharmaceuticals, Inc.	$ (205,275)	$ (176,063)	$ (140,848)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details