Convertible Senior Note Repurchase Price As Percentage Of Principal Amount

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Debt Instrument Debt Covenants Debt Default Holder Percent To Declare All Notes Due Minimum

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Number Of Allowable Board Of Director Appointments

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Ownership Percentage, Board Of Directors Appointment Threshold

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Ownership Percentage, Board Of Directors Observer Appointment Threshold

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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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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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount, after accumulated amortization, of debt discount.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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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 cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The cash inflow from the additional capital contribution to the entity.

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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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Number of new stock issued during the period.

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Debt - Additional Information (Detail)				1 Months Ended	3 Months Ended		6 Months Ended
Debt - Additional Information (Detail)	Jun. 28, 2018 shares	May 09, 2018 USD ($) appointment shares $ / shares	Oct. 14, 2015 $ / shares	Oct. 31, 2015 USD ($)	Jun. 30, 2018 USD ($) shares	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) shares	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) shares	Jun. 08, 2017 shares
Debt Conversion [Line Items]
Proceeds from issuance of convertible senior notes							$ 10,000,000	$ 0
Common stock, shares authorized (in shares) \| shares					230,000,000		230,000,000		230,000,000	230,000,000
Proceeds from issuance of common stock, net of commission		$ 10,000,000					$ 0	73,125,000
Stock issued during period, shares, new issues \| shares		2,200,000
Interest expense					$ 1,300,000	$ 1,300,000	63,000,000	$ 63,000,000
Notes, carrying amount					130,088,000		130,088,000		$ 125,000,000
Notes, fair value					$ 133,800,000		$ 133,800,000		$ 155,400,000
Convertible Senior Notes, due 2020
Debt Conversion [Line Items]
Proceeds from issuance of convertible senior notes				$ 125,000,000
Minimum aggregate principal amount outstanding for declaration notice					25.00%		25.00%
Conversion ratio			0.2673797
Conversion price, per share (in dollars per share) \| $ / shares			$ 3.74
Repurchase price percentage of the principal amount							100.00%
Convertible Senior Notes, due 2020 \| Default (other than certain events of bankruptcy, insolvency or reorganization)
Debt Conversion [Line Items]
Redemption percentage							100.00%
Convertible Senior Notes, due 2020 \| Events of bankruptcy, insolvency or reorganization
Debt Conversion [Line Items]
Redemption percentage							100.00%
Convertible Senior Notes due 2021
Debt Conversion [Line Items]
Conversion ratio		0.215983
Asset-backed Credit Facility
Debt Conversion [Line Items]
Line of credit facility, maximum borrowing capacity		$ 40,000,000
Convertible Debt \| Convertible Senior Notes due 2021
Debt Conversion [Line Items]
Conversion price, per share (in dollars per share) \| $ / shares		$ 4.63
Senior notes issued		$ 164,746,000
Shares, outstanding (in shares) \| shares		33,400,000
Stock issued during period, shares, new issues \| shares	4,000,000	4,000,000
Debt discount					$ 36,000,000		$ 36,000,000
Baupost
Debt Conversion [Line Items]
Number of allowable board of director appointments \| appointment		1
Ownership percentage, board of directors appointment threshold		20.00%
Ownership percentage, board of directors observer appointment threshold		10.00%