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Significant Accounting Policies, Convertible Debt (Details) | Sep. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2019
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0.125 Percent Convertible Senior Notes [Member] |  |  |
Convertible Debt [Abstract] |  |  |
Interest rate on convertible senior notes | 0.125% | 0.125% |
1 Percent Convertible Senior Notes [Member] |  |  |
Convertible Debt [Abstract] |  |  |
Interest rate on convertible senior notes | 1.00% | 1.00% | 1.00%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- References No definition available. + Details
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- Details
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- Details
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