Inventory Valuation Reserves, Assumptions, Forecasted Demand Period

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Amount of valuation reserve for inventory.

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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.

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No definition available.

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- Definition

Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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Nature of Business, Liquidity, Basis of Presentation and Summary of Significant Accounting Policies - Other Components of Balance Sheet (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Net Investment Income [Line Items]
Short-term investments	$ 0	$ 104,350,000	$ 104,350,000	$ 4,494,000	$ 15,703,000	$ 20,138,000
Interest rate percentage	6.00%
Inventory reserve	$ 14,600,000		13,000,000
US Treasury Bill Securities
Net Investment Income [Line Items]
Short-term investments	$ 0		$ 104,400,000
Minimum
Net Investment Income [Line Items]
Future demand period	12 months
Maximum
Net Investment Income [Line Items]
Future demand period	24 months