Convertible Notes rate conversion consecutive trading days (in days)

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- Definition

Convertible note rate conversion trading days (in days)

+ References

No definition available.

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Maximum percent of common stock closing price and conversion rate to convert note.

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- Definition

The minimum conversion price of convertible notes in order for holders to convert their notes.

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- Definition

Debt discount recorded to additional paid in capital

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- Definition

Debt discount recorded to deferred tax liability

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- Definition

Estimated market interest rate for similar nonconvertible instrument

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No definition available.

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- Definition

The amount of principal tendered which a $5.00 cash payment is made per each to convert the Series 2012 notes to February 2015 notes.

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No definition available.

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Repurchase price upon fundamental change as described in 2021 Notes indenture

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- Definition

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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- Definition

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

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- Definition

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

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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Amount of the required periodic payments applied to interest.

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Amount of the required periodic payments applied to principal.

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- Definition

Fair value amount of debt instrument that was repurchased.

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No definition available.

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Amount, after accumulated amortization, of debt discount.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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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 issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Convertible Notes (Narrative) (Detail)				6 Months Ended
Convertible Notes (Narrative) (Detail)	Feb. 02, 2018 USD ($)	Nov. 21, 2016 USD ($)	Feb. 11, 2014 USD ($)	Jun. 30, 2019 USD ($) $ / shares	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2018	Nov. 22, 2016 USD ($) $ / shares	Nov. 20, 2015 USD ($)	Feb. 12, 2014 USD ($)
Debt Instrument [Line Items]
Principal amount a $5 incentive cash payment per each to convert debt				$ 1,000
Convertible note rate conversion trading days (in days)				0
Convertible Notes rate conversion consecutive trading days (in days)				$ 30
Minimum conversion price percent for note conversion (in Percent)				130.00%
Repurchase price upon fundamental change as described in 2021 Notes indenture				100.00%
Interest Paid, Including Capitalized Interest, Operating and Investing Activities				$ 2,063,000	$ 4,591,000
February 2018 Notes [Member]
Debt Instrument [Line Items]
Convertible notes										$ 300,000,000
Debt Instrument, Interest Rate, Stated Percentage							4.00%
Net proceeds from the issuance of convertible notes			$ 290,200,000
Debt Instrument, Repurchase Amount								$ 120,000,000	$ 53,600,000
Repayments of Debt	$ 129,000,000
Debt Instrument, Periodic Payment, Principal	126,400,000
Debt Instrument, Periodic Payment, Interest	$ 2,600,000
December 2021 Notes [Member]
Debt Instrument [Line Items]
Convertible notes				$ 128,520,000		$ 124,644,000		$ 150,000,000	$ 150,000,000
Debt Instrument, Interest Rate, Stated Percentage				2.75%				2.75%
Unamortized discount of liability component				$ (21,480,000)		(25,356,000)		$ (4,300,000)
Debt discount recorded to additional paid in capital								23,800,000
Debt discount recorded to deferred tax liability								$ 12,800,000
Maximum percent of common stock closing price and conversion rate to convert note (in Percent)				98.00%
Debt Instrument, Interest Rate, Effective Percentage								3.40%
Convertible notes, conversion price (in Dollars per Share) \| $ / shares								$ 3.81
Estimated market interest rate for similar nonconvertible instrument								9.50%
Debt instrument, convertible, remaining amortization period (in Duration)				2 years 5 months 5 days
Net proceeds from the issuance of convertible notes		$ 145,700,000
Debt Instrument, Face Amount				$ 150,000,000		$ 150,000,000
Conversion Rate per $1,000 Principal Amount (in Ratio)		262.2951
Proceeds from Issuance of Warrants		$ 14,400,000
Purchased Call Options [Member]
Debt Instrument [Line Items]
Convertible notes, conversion price (in Dollars per Share) \| $ / shares				$ 4.88