STOCK-BASED EMPLOYEE COMPENSATION (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 60,164	$ 35,168	$ 114,172	$ 73,971
Restricted Stock Units and Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized estimated compensation expense, unvested share-based awards	$ 362,100		$ 362,100
Total future compensation cost related to unvested share-based awards, expected period of recognition			1 year 10 months
Granted (in shares)			175,741
Granted (in dollars per share)			$ 1,235.69
Unvested at June 30, 2015	590,842		590,842		570,315
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			73,019
Vesting period (in years)			3 years
Grant date fair value			$ 90,400
Granted (in dollars per share)			$ 1,237.90
Performance Share Units 2015 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			102,722
Grant date fair value			$ 126,800
Granted (in dollars per share)			$ 1,234.11
Estimated number of probable shares to be issued (in shares)	101,888		101,888
Maximum shares that could be issued (in shares)	234,544		234,544
Minimum shares that could be issued (in shares)	49,702		49,702
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			3 years
Performance Share Units 2014 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)					72,277
Grant date fair value					$ 96,100
Granted (in dollars per share)					$ 1,329.11
Estimated number of probable shares to be issued (in shares)	109,725		109,725
Maximum shares that could be issued (in shares)	140,746		140,746
Minimum shares that could be issued (in shares)	48,652		48,652
Unvested at June 30, 2015	69,609		69,609
Performance Share Units 2013 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)						104,865
Grant date fair value						$ 74,400
Granted (in dollars per share)						$ 709.74
Estimated number of probable shares to be issued (in shares)	186,264		186,264
Maximum shares that could be issued (in shares)	214,757		214,757
Minimum shares that could be issued (in shares)	38,688		38,688
Unvested at June 30, 2015	98,857		98,857
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,600	$ 2,700	$ 15,000	6,800
Total future compensation cost related to unvested share-based awards, expected period of recognition			1 year 5 months
Exercised (in shares)			31,986
Exercised (in dollars per share)			$ 362.28
Stock options exercised, total intrinsic value			$ 26,400	$ 33,900
Ending balance (in shares)	111,834.000		111,834.000		146,385
Weighted Average Exercise Price (in dollars per share)	$ 377.83		$ 377.83		$ 380.05
Aggregate Intrinsic Value	$ 86,508		$ 86,508		$ 111,277
Weighted Average Remaining Contractual Term, Exercisable			5 years 5 months
Share Based Compensation Arrangement By Share Based Payment Award Options Vested in Period Number Of Shares			22,352	15,363
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value			$ 15,100	$ 6,500
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options	$ 20,300		20,300
Awards assumed in acquisitions [Member] | Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Acquisition date fair value of assumed options			$ 1,400
Acquisition date fair value per share of assumed stock options			$ 1,015.81