Long-term Debt (Narrative) (Details) - USD ($)	1 Months Ended	12 Months Ended
Oct. 31, 2017	Mar. 31, 2018
Debt Instrument [Line Items]
Equity options, purchase price as a percentage of share price	105.00%
Equity commitment, number of consecutive trading days used for measuring share price	5 days
Equity option	$ 20,000,000
Equity option to be exercised in the current year	$ 10,000,000
Common Shares
Debt Instrument [Line Items]
Warrants exercisable as a percentage of principal amount of loan	3.00%
Private Placement
Debt Instrument [Line Items]
Shares purchased by NovaQuest (in shares)	138,361
Shares purchased by NovaQuest	$ 2,000,000
Line of Credit \| NovaQuest Securities Purchase Agreement
Debt Instrument [Line Items]
Maximum borrowing commitment	60,000,000
Equity commitment related to note issuance	20,000,000
Minimum borrowing commitment	30,000,000
Debt issued	$ 6,000,000
Interest rate	15.00%
Quarterly interest rate	5.00%
Deferred interest rate	10.00%
Default interest rate	5.00%
Financing expenses	$ 1,000,000
Amortized deferred financing costs		$ 200,000
Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Maximum borrowing commitment	$ 40,000,000
Interest rate	8.25%
Default interest rate	5.00%
Amortized deferred financing costs		500,000
Principal amount funded	$ 25,000,000	$ 15,000,000
Current interest rate		8.75%
End of term charge	6.55%
Term Loan \| Hercules Loan Agreement \| Prime Rate
Debt Instrument [Line Items]
Variable interest rate	4.00%
Tranche 1 \| Common Shares
Debt Instrument [Line Items]
Number of securities exercisable by warrant (in shares)	49,800
Exercise price of warrants (in USD per share)	$ 15.06
Fair value of warrant on date of issuance	$ 500,000
Tranche 1 \| Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Financing expenses	1,300,000
Discount	$ 2,100,000
Tranche 2 \| Common Shares
Debt Instrument [Line Items]
Number of securities exercisable by warrant (in shares)	23,910
Exercise price of warrants (in USD per share)	$ 18.82
Fair value of warrant on date of issuance	$ 300,000
Tranche 2 \| Term Loan \| Hercules Loan Agreement
Debt Instrument [Line Items]
Discount	$ 1,300,000

Class of Warrant or Right, Maximum Percentage of Principal of Debt Instrument Allowed to be Exercisable

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Debt Instrument, Default Interest Rate

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Debt Instrument, End of Term Charge Rate

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Debt Instrument, Equity Commitment

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Debt Instrument, Interest Rate, Stated Deferred Rate

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Debt Instrument, Interest Rate, Stated Quarterly Rate

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Equity Commitment, Number of Consecutive Trading Days Used to Measure Price

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Line of Credit Facility, Minimum Required Borrowings

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Option Indexed to Issuer's Equity, Minimum Nominal Value Expected to Exercised in Current Year

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Option Indexed to Issuer's Equity, Nominal Value

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Option Indexed to Issuer's Equity, Price as a Percentage of Share Price

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Amount of amortization expense attributable to debt issuance costs.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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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, after accumulated amortization, of debt discount.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Fair value portion of warrants not settleable in cash classified as equity.

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