STOCK INCENTIVE PLANS (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for grant under stock incentive plans (in shares)	2,700,000
Pretax stock-based compensation expense	$ 31,000	$ 35,000	$ 43,000
Income tax benefits recognized in earnings for stock-based compensation expense	$ 25,000	$ 11,000	$ 13,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at January 1 (in shares)	2,124,036	2,226,286	2,582,804
Granted (in shares)	306,206	294,874	294,522
Exercised (in shares)	(409,269)	(317,110)	(587,441)
Canceled or expired (in shares)	(87,260)	(80,014)	(63,599)
Outstanding at December 31 (in shares)	1,933,713	2,124,036	2,226,286
Weighted Average Price Per Share [Abstract]
Outstanding at January 1, weighted average price per share (in dollars per share)	$ 186.59	$ 169.96	$ 149.01
Granted, weighted average price per share (in dollars per share)	230.97	234.25	232.20
Exercised, weighted average price per share (in dollars per share)	115.35	108.28	105.08
Canceled or expired, weighted average price per share (in dollars per share)	222.00	210.01	216.76
Outstanding at December 31, weighted average price per share (in dollars per share)	$ 207.10	$ 186.59	$ 169.96
Options exercisable outstanding at January 1 (in shares)	1,346,707	1,411,460	1,647,903
Options exercisable outstanding at December 31 (in shares)	1,375,844	1,346,707	1,411,460
Stock Options Exercised [Abstract]
Fair value of options exercised	$ 10,816	$ 8,086	$ 14,423
Total intrinsic value of options exercised	47,332	35,800	73,671
Fair value of options vested	23,503	14,535	16,047
Proceeds from stock options exercised	$ 47,181	$ 34,573	$ 61,863
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Expiration period	10 years
Stock Options Exercised [Abstract]
Unrecognized compensation	$ 8,900
Weighted average period to recognize (in years)	1 year 9 months 18 days

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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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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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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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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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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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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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of stock value of such awards forfeited. Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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