STOCK-BASED EMPLOYEE COMPENSATION (Tables)

6 Months Ended

Jun. 30, 2015

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Activity of unvested restricted stock units and performance share units

Restricted Stock Units and Performance Share Units

The following table summarizes the activity of restricted stock units and performance share units ("share-based awards") during the six months ended June 30, 2015: 

Share-Based Awards	Shares		Weighted-Average Grant Date Fair Value
Unvested at December 31, 2014	570,315			$	912.26
Granted	175,741			$	1,235.69
Vested	(140,732	)		$	707.08
Performance Share Units Adjustment	1,056			$	1,191.41
Forfeited	(15,538	)		$	1,059.52
Unvested at June 30, 2015	590,842			$	1,056.85

Schedule of share-based compensation, stock options, activity

Stock Options

The following table summarizes the activity for the six months ended June 30, 2015 for employee stock options: 

Assumed Employee Stock Options	Number of Shares		Weighted-Average Exercise Price			Aggregate  Intrinsic Value (in thousands)			Weighted-Average Remaining Contractual Term (in years)
Balance, December 31, 2014	146,385			$	380.05		$	111,277	6.5
Assumed in acquisitions	1,422			$	230.37
Exercised	(31,986	)		$	362.28
Forfeited	(3,987	)		$	531.10
Balance, June 30, 2015	111,834			$	377.83		$	86,508	6.0
Vested and exercisable as of June 30, 2015	79,704			$	329.75		$	65,486	5.4
Vested and exercisable as of June 30, 2015 and unvested expected to vest thereafter, net of estimated forfeitures	111,588			$	376.79		$	86,433	6.0