Financial Instruments (Other Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Investment Holdings [Line Items]
Life Insurance Contracts	$ 41,992	$ 41,074
Other Investments	154,502	144,917
Equity Mutual Fund [Member]
Investment Holdings [Line Items]
Fair Value	39,618	40,660
Fixed Income Mutual Fund [Member]
Investment Holdings [Line Items]
Fair Value	72,253	62,339
Marketable Equity Securities [Member]
Investment Holdings [Line Items]
Fair Value	$ 639	$ 844

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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