Number of fractional shares issued.

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- Definition

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

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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No definition available.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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No definition available.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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- Definition

Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Stock-Based Compensation - Additional Information (Detail)		1 Months Ended					12 Months Ended
	Aug. 11, 2017 shares	Mar. 31, 2018 shares	Feb. 29, 2016 shares	Feb. 28, 2015 shares	Mar. 31, 2014 shares	Feb. 28, 2013 shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Sep. 05, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Special cash dividend paid \| $							$ 140,000,000
Dividend payable date							May 26, 2017
Dividend payable, date of record							May 17, 2017
Incremental compensation expense \| $							$ 6,900,000
Reverse stock split description							Reverse Split, every ten shares of common stock issued and outstanding was converted into one share of common stock
Reverse stock split, conversion ratio	0.1
Common stock, shares issued	132,800,000						13,343,000	13,343,000	13,280,000
Common stock, shares outstanding	132,800,000						13,343,000	13,343,000	13,280,000
Common stock, shares authorized	200,000,000						30,000,000	20,000,000	20,000,000
Number of fractional shares issued									0
Preferred stock, shares issued							0	0	0
Preferred stock, shares outstanding							0	0	0
Number of Options, Granted							1,190,000
Weighted-average grant date fair value per share of stock options \| $ / shares							$ 4.47	$ 4.07
Aggregate intrinsic value of options exercised \| $							$ 0	$ 2,400,000
Unrecognized stock-based compensation expense related to nonvested stock options \| $							$ 5,700,000
Weighted average period over which unrecognized stock-based compensation expense is expected to be recognized							2 years 3 months 18 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term							10 years
Stock Incentive Plan 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional common stock available for issuance (in shares)		500,000	400,000	400,000	400,000	300,000
Shares of common stock available for grant (in shares)							300,000
Number of Options, Granted							1,200,000	2,100,000
Stock Incentive Plan 2011 [Member] \| Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vesting period							3 years
Stock Incentive Plan 2011 [Member] \| Non-Employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vesting period							1 year