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Sum of the carrying amounts as of the balance sheet date of all investments.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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Fair Value of Financial Instruments Fair Value of Non-marketable securities (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Other Investment Not Readily Marketable [Line Items]
Unrealized Gains		$ 1,966	$ 1,071
Payments to Acquire Investments	$ 600
Preferred Stock [Member]
Other Investment Not Readily Marketable [Line Items]
Investments					$ 2,500
Convertible Debt Securities [Member]
Other Investment Not Readily Marketable [Line Items]
Investments			600	$ 600
Current Assets [Member]
Other Investment Not Readily Marketable [Line Items]
Unrealized Gains		1,163	246
Long-term investments
Other Investment Not Readily Marketable [Line Items]
Unrealized Gains		792	825
US government agencies \| Long-term investments
Other Investment Not Readily Marketable [Line Items]
Unrealized Gains		$ 544	$ 370