Investments - Non-Current Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Non-current investments [Abstract]
Equity and fixed income mutual funds	$ 25,949	$ 24,610
Life insurance policies	4,653	4,621
Other (primarily cost-method) investments	19,044	34,019
Total non-current investments	$ 49,646	$ 63,250

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Amount of investments classified as other.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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