The value of the conversion obligation in excess of the par value of the convertible notes.

No definition available.

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- Definition

Expiration, mandatory redemption, or due date, in CCYY-MM-DD format, of the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction.

+ References

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

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- Definition

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

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- Definition

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

+ References

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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.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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- Definition

Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

+ References

No definition available.

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- Definition

The cash outflow from the repayment 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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- Definition

Number of shares issued during the period as a result of the conversion of convertible securities.

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Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

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Debt - 2010 Convertible Notes (Details Textual)	1 Months Ended	12 Months Ended
Debt - 2010 Convertible Notes (Details Textual)	Mar. 31, 2017 USD ($) shares	Dec. 31, 2017 USD ($) Tradingday	Dec. 31, 2016 USD ($)	Mar. 31, 2010 USD ($)
Debt Instrument [Line Items]
Loss on repurchase of convertible notes			$ (8,651,000)
Intrinsic value of conversion obligation			39,841,000
Convertible notes cash paid			215,676,000
Senior Subordinated Convertible Notes 2010
Debt Instrument [Line Items]
Senior subordinated convertible notes face amount				$ 150,000,000
Interest rate on senior subordinated convertible notes		3.00%		3.00%
Maturity period		Mar. 01, 2017
Aggregate principal amount of convertible notes repurchased			115,300,000
Amount paid to purchase aggregate principal amount			215,600,000
Loss on repurchase of convertible notes			8,700,000
Principal outstanding on Convertible Notes			34,722,000
Debt instrument, convertible, terms of conversion feature		Prior to September 1, 2016, holders of the 2010 Convertible Notes could convert their securities at any time in the fiscal quarter following the period in which the price of our common stock traded over 130% of the conversion price for at least 20 consecutive trading days in the last 30 trading days of a fiscal quarter. Beginning September 1, 2016, the holders of the 2010 Convertible Notes could elect to convert their securities at any time, with settlement occurring on March 1, 2017.
Debt instrument, convertible, settlement date		Mar. 01, 2017
Rate of conversion price		130.00%
Debt instrument, convertible, threshold trading days \| Tradingday		20
Debt instrument, convertible, threshold consecutive trading days \| Tradingday		30
Intrinsic value of conversion obligation		$ 40,000,000
Convertible notes cash paid	$ 34,800,000
Settlement of conversion obligation by common shares delivered from treasury stock \| shares	694,240
Settlement of conversion obligation in excess of par value	$ 28,800,000
2010 Convertible Notes Converted by Holders
Debt Instrument [Line Items]
Aggregate principal amount of convertible notes repurchased			50,000
Amount paid to purchase aggregate principal amount			$ 100,000