Fair Value Measurements - Narrative (Details) - USD ($) |
3 Months Ended | 12 Months Ended | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Mar. 31, 2019 |
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2019 |
Mar. 31, 2018 |
Mar. 31, 2017 |
Sep. 28, 2016 |
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| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||
| Secured debenture issuance costs and discount | $ 0 | $ 1,827,000 | $ 0 | $ 1,827,000 | ||||||||
| Convertible notes, net of debt issuance costs and discounts of $0 and $1,827, respectively | $ 0 | $ 3,873,000 | $ 0 | $ 3,873,000 | ||||||||
| Stock price (in dollars per share) | $ 3.5 | $ 2.01 | $ 3.5 | $ 2.01 | $ 0.94 | |||||||
| Change in fair value of convertible note embedded derivative liability | $ (2,104,000) | $ (1,476,000) | $ 952,000 | $ 1,620,000 | $ (1,249,000) | $ (1,658,000) | $ (3,344,000) | $ (1,308,000) | $ (1,008,000) | $ (7,559,000) | $ 475,000 | |
| Change in fair value of convertible note embedded derivative liability | (5,720,000) | $ (1,651,000) | $ 926,000 | $ 1,570,000 | (682,000) | $ (898,000) | $ (1,164,000) | $ (464,000) | 4,875,000 | 3,208,000 | $ (147,000) | |
| Convertible Notes Payable | ||||||||||||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||
| Original discount | $ 4,916,000 | |||||||||||
| Debt face amount | 0 | 5,700,000 | 0 | 5,700,000 | $ 16,000,000 | |||||||
| Interest rate | 8.75% | |||||||||||
| Issuance of common stock related to debt | 5,700,000 | 10,300,000 | ||||||||||
| Secured debenture issuance costs and discount | 0 | $ 1,827,000 | 0 | $ 1,827,000 | ||||||||
| Convertible notes, net of debt issuance costs and discounts of $0 and $1,827, respectively | $ 0 | $ 0 | ||||||||||
| X | ||||||||||
- Definition The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after accumulated amortization, of debt discount. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of unamortized debt discount (premium) and debt issuance costs. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expense (income) related to adjustment to fair value of warrant liability. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Price of a single share of a number of saleable stocks of a company. No definition available.
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- Details
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