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Fair Value Measurements - Estimated Fair Value of Equity Securities Assumptions (Details) |  | 12 Months Ended
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Apr. 03, 2018 | Dec. 31, 2018
Discount for Lack of Marketability [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Valuation assumptions, measurement input | 30 | 35
Liquidity of Shares [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Valuation assumptions, measurement input term | 1 year 5 months 12 days | 1 year 5 months 12 days
Liquidation [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Valuation assumptions, measurement input | 65 | 20
Near-term Sale [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Valuation assumptions, measurement input | 5 | 5
Near-term Financing [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items] |  |
Valuation assumptions, measurement input | 30 | 75

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- Definition Value of input used to measure investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + 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 (bbb)(2) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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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. + Details
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- Definition Equity securities (Fv-Ni), term. + References No definition available. + Details
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