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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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