COMMON STOCK AND EARNINGS PER SHARE (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
COMMON STOCK AND EARNINGS PER SHARE
Weighted-average number of common shares outstanding - basic	47,647,961	47,200,099
Potentially dilutive shares resulting from stock plans	705,086	848,895
Weighted-average number of common shares outstanding - diluted	48,353,047	48,048,994
Antidilutive equity awards number of shares not included in the weighted-average common shares - diluted	0	164,000
Earnings per share, other disclosures
Repurchase of common stock, shares	287,689	237,628
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	271,426
Purchase of common stock for treasury	$ 6,067	$ 3,691
Exercise of stock options, shares	274,346	1,590
Proceeds from the issuance of common stock	$ 3,826	$ 36
Vested (in shares)	267,830	496,191

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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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The cash outflow to reacquire common stock during the period.

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The cash inflow from the additional capital contribution to the entity.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Number of share options (or share units) exercised during the current period.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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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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