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Financial Instruments (Details Textual)	3 Months Ended	6 Months Ended
	Mar. 31, 2021	Jun. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Average maturity of marketable securities, months	12 months	11 months

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- Definition

Average remaining time to maturity of marketable debt securities, available-for-sale securities.

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No definition available.

+ Details

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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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