Face (par) amount of debt instrument at time of issuance.

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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, after accumulated amortization, of debt discount.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Notes Payable and Stock Purchase Warrants - Carrying amount of notes payable (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Jul. 31, 2019	Mar. 31, 2018
Solar Term Loan
Debt Instrument [Line Items]
Aggregate principal amount		$ 45,000
Debt Discount		(1,466)
Issuance costs		(100)
Carrying Amount		43,434
2023 Notes
Debt Instrument [Line Items]
Aggregate principal amount	$ 15,700	15,700		$ 53,000
Debt Discount	(3,624)	(3,900)
Carrying Amount	12,076	11,800
2025 Notes
Debt Instrument [Line Items]
Aggregate principal amount	82,000	82,000	$ 82,000
Debt Discount	(45,006)	(46,482)
Issuance costs	(686)	(708)
Carrying Amount	$ 36,308	$ 34,810