Forgiven unsecured term loans.

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount of gain (loss) on sale or disposal of other assets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for translation gain (loss) realized upon the sale or liquidation of an investment in a foreign entity and foreign currency hedges that are designated and qualified as hedging instruments for hedges of the foreign currency exposure of a net investment in a foreign operation.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Assets Held for Sale, Discontinued Operations and Disposals - Additional Information (Details) - USD ($) $ in Thousands			1 Months Ended	12 Months Ended
	Jan. 22, 2020	Jun. 07, 2019	Aug. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Sep. 16, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on sale of subsidiary				$ (13,709)	$ 1,614
Gain on sale of other assets						$ 2,883
SoLayTec \| Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on sale of subsidiary		$ 1,600
Tempress \| Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Unsecured term loan, principal amount	$ 2,250
Pre-tax loss on sale	10,900
Previously recorded accumulated foreign currency translation losses recognized	$ 7,200
Forgave unsecured term loans				500
R2D \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on sale of subsidiary				$ (2,800)
Kingstone Hong Kong
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity method investment, ownership percentage								15.00%
Equity method investment at fair value								$ 2,700
Equity method investment at carrying value							$ 2,600
Proceeds from sale of equity method investment			$ 5,700
Gain on sale of other assets						$ 2,900