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Revenue From Contract With Customer, Product Return Period

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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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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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Summary of Significant Accounting Policies - Narrative (Details)	1 Months Ended	12 Months Ended
	Sep. 12, 2017	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Jan. 01, 2019 USD ($)	Aug. 14, 2017
Debt Instrument [Line Items]
Other-than-temporary impairment losses		$ 0
Realized gains or losses on the sale of securities		0	$ 0
Impairment charges		$ 0
Number of operating segments \| segment		1
Number of geographic segments \| segment		1
Expected dividend yield (as a percent)		0.00%
Right of use assets - operating leases		$ 6,704,000		$ 8,289,000
Operating lease, liability		$ 6,779,000	$ 0
3.00% Convertible notes \| Convertible debt
Debt Instrument [Line Items]
Debt instrument stated rate	3.00%	3.00%			3.00%
Debt instrument remaining discount amortization period	7 years	7 years
Accounting Standards Update 2016-02
Debt Instrument [Line Items]
Right of use assets - operating leases				8,289,000
Operating lease, liability				$ 8,300,000
Minimum
Debt Instrument [Line Items]
Revenue from contract with customer, product return period		6 months
Maximum
Debt Instrument [Line Items]
Revenue from contract with customer, product return period		12 months