Outstanding Debt - Summary of Various Notes Issued (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Principal		$ 4.5
Unamortized discount		(2.5)
Carrying value		$ 2.0
December 4, 2018 [Member]
Debt Instrument [Line Items]
Maturity date	Dec. 04, 2018
Interest rate		8.00%
Conversion price		$ 1.75
Principal		$ 1.7
Carrying value		$ 1.7
March 1, 2019 [Member]
Debt Instrument [Line Items]
Maturity date	Mar. 01, 2019
Interest rate		8.00%
Conversion price		$ 1.75
Principal		$ 0.6
Unamortized discount		(0.5)
Carrying value		$ 0.1
March 21, 2019 [Member]
Debt Instrument [Line Items]
Maturity date	Mar. 21, 2019
Interest rate		8.00%
Conversion price		$ 1.75
Principal		$ 0.4
Unamortized discount		(0.2)
Carrying value		$ 0.2
December 4, 2019 [Member]
Debt Instrument [Line Items]
Maturity date	Dec. 04, 2019
Interest rate		8.00%
Conversion price		$ 1.75
Principal		$ 0.9
Unamortized discount		$ (0.9)
March 1, 2020 [Member]
Debt Instrument [Line Items]
Maturity date	Mar. 01, 2020
Interest rate		8.00%
Conversion price		$ 1.75
Principal		$ 0.8
Unamortized discount		$ (0.8)
March 21, 2020 [Member]
Debt Instrument [Line Items]
Maturity date	Mar. 21, 2020
Interest rate		8.00%
Conversion price		$ 1.75
Principal		$ 0.1
Unamortized discount		$ (0.1)
Long Term Convertible Notes Payable [Member] \| 8.0% July 2019 Notes [Member]
Debt Instrument [Line Items]
Interest rate	8.00%
Conversion price	$ 1,500
Principal	$ 2.0

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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

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