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Marketable Securities and Fair Value Disclosures - Summary of Marketable securities (Details) - USD ($) | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Fair Value | $ 0 |
Short-term available-for-sale securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost |  | $ 3,052,000
Gross Unrealized Losses |  | (2,000)
Fair Value |  | 3,050,000
Short-term available-for-sale securities | Corporate bonds |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost |  | 3,052,000
Gross Unrealized Losses |  | (2,000)
Fair Value |  | $ 3,050,000

X
- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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