Earnings Per Common Share-Reconciliation of Basic and Diluted EPS Denominators (Details) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Reconciliation of the basic and diluted EPS denominators
Basic weighted-average common shares	32,604	32,084	32,514	32,114
Dilutive effect of 2010 Convertible Notes	813		778
Dilutive effect of Stock Warrants	4		1
Diluted weighted-average common shares	33,996	32,664	33,858	32,553
Employee Stock Option
Reconciliation of the basic and diluted EPS denominators
Dilutive effect				1
Restricted Stock
Reconciliation of the basic and diluted EPS denominators
Dilutive effect	575	580	565	438

Incremental common shares attributable to warrants.

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- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

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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.

+ References

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

-Publisher FASB

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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.

+ References

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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