Marketable Securities	6 Months Ended
Mar. 31, 2022
Marketable Securities [Abstract]
Marketable Securities	9. Marketable Securities We did not hold any marketable securities as of September 30, 2021 or March 31, 2022. In December 2020, we sold our remaining marketable securities to partially fund the Arena acquisition, resulting in proceeds of $56.2 million. Neither gross realized gains nor gross realized losses related to the sale were material.

The entire disclosure for investments in certain debt and equity securities.

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-SubTopic 320
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-Publisher FASB
-Name Accounting Standards Codification
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1403
-Paragraph (b)

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