Fair Value of Financial Instruments Marketable Securities (Details) - Marketable Securities [Member] - Fair Value, Recurring [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investment, Additional Purchase	$ 0	$ 8,995
Beginning Balance	94,727	49,037
Ending Balance	55,602	94,727
Investment, Fair Value Adjustment	(28,647)	34,240
Investment, Foreign Current Translation Adjustment	(11,414)	816
Stock Issued During Period, Value, Dividend Reinvestment Plan	$ 936	$ 1,639

Investment, Additional Purchase

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- Definition

Investment, Fair Value Adjustment

+ References

No definition available.

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- Definition

Investment, Foreign Current Translation Adjustment

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Value of stock issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the holder of the stock to reinvest dividends paid to them by the entity on new issues of stock by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

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