Income Per Share - Weighted Average Number of Common Shares Outstanding (Detail) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Weighted average shares outstanding - basic	51,123	50,623
Effect of dilutive stock-based compensation	398	573
Effect of convertible notes		7,152
Effect of common stock warrants		5,725
Weighted average shares outstanding - diluted	51,521	64,073

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Warrant

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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