EQUITY (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Treasury Stock
Shares Repurchased	34,293us-gaap_TreasuryStockSharesAcquired	163,222us-gaap_TreasuryStockSharesAcquired	9,175us-gaap_TreasuryStockSharesAcquired
Aggregate Cost	$ 2,160,000	$ 8,103,000	$ 344,000
Average Repurchase Price (in dollars per share)	$ 63.01	$ 49.64	$ 37.51
Stock-based compensation
Number of shares reserved to be granted under the plan	2,000,000
Number of Options
Exercised (in shares)	(43,034)	(303,536)	(62,575)
Stock options
Stock-based compensation
Expiration term	10 years
Vesting period	4 years
Number of Options
Outstanding at the beginning of the period (in shares)	401,287	720,448
Exercised (in shares)	(43,034)	(303,536)
Forfeited- Vested (in shares)		(11,625)
Forfeited- Unvested (in shares)	(7,000)	(4,000)
Outstanding at the end of the period (in shares)	351,253	401,287	720,448
Vested and expected to vest at the end of the period (in shares)	351,142	398,036
Exercisable at the end of the period (in shares)	290,128	241,662
Weighted Avg. Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 36.63	$ 34.31
Exercised (in dollars per share)	$ 37.68	$ 30.64
Forfeited- Vested (in dollars per share)		$ 46.01
Forfeited- Unvested (in dollars per share)	$ 34.22	$ 45.22
Outstanding at the end of the period (in dollars per share)	$ 36.55	$ 36.63	$ 34.31
Vested and expected to vest at the end of the period (in dollars per share)	$ 36.56	$ 35.86
Exercisable at the end of the period (in dollars per share)	$ 36.81	$ 35.86
Weighted Average Remaining Contractual Term
Outstanding	5 years	6 years
Vested and expected to vest	5 years	6 years
Exercisable	4 years 7 months 6 days	5 years 2 months 12 days
Aggregate Intrinsic Value
Outstanding	10,901,529	8,000,149
Vested and expected to vest	10,987,590	7,934,478
Exercisable	8,929,815	5,004,299
Unamortized stock based compensation
Unamortized stock based compensation	400,000
Weighted-average period for recognition of unamortized stock-based compensation cost	1 year
Stock-based compensation, additional disclosures
Weighted-average fair value of options granted (in dollars per share)			$ 15.27
Aggregate intrinsic value of options exercised	1,098,336,000	6,111,000	938,000
Cash proceeds received upon exercise of options	1,621,000	2,669,000	1,452,000
Excess tax benefits from share-based compensation	513,000	2,101,000	(362,000)
Weighted-average assumptions using Black-Scholes option-pricing model for estimating fair value of each option granted
Risk-free interest rate (as a percent)			1.40%
Expected dividend yield (as a percent)			2.50%
Expected life			6 years 3 months
Expected volatility (as a percent)			53.00%
Stock compensation expense
Stock compensation expense	900,000	1,400,000	1,800,000
Restricted Stock
Stock-based compensation
Vesting period	4 years
Unamortized stock based compensation
Unamortized stock based compensation	8,100,000
Weighted-average period for recognition of unamortized stock-based compensation cost	2 years 9 months 18 days
Stock compensation expense
Stock compensation expense	$ 3,400,000	$ 3,100,000	$ 1,800,000
Shares
Unvested at the beginning of the period (in shares)	154,519	103,853
Granted (in shares)	109,318	100,902	72,083
Forfeited (in shares)	(8,500)	(250)
Vested and issued (in shares)	(60,194)	(49,986)
Unvested at the end of the period (in shares)	195,143	154,519	103,853
Weighted Avg. Fair Value
Unvested at the beginning of the period (in dollars per share)	$ 44.04	$ 39.63
Granted (in dollars per share)	$ 64.73	$ 48.54
Forfeited (in dollars per share)	$ 51.44	$ 46.85
Vested and issued (in dollars per share)	$ 44.61	$ 43.96
Unvested at the end of the period (in dollars per share)	$ 55.13	$ 44.04	$ 39.63
2008 Equity Incentive Plan \| Restricted Stock
Stock-based compensation
Vesting period	4 years

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Unrecognized cost of unvested share-based compensation awards.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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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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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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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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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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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Number of non-vested options forfeited.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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