STOCKHOLDERS' EQUITY AND SHARE-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2012

STOCKHOLDERS' EQUITY AND SHARE-BASED COMPENSATION

Schedule of the weighted average assumptions used to determine the fair value of options as of the grant date

	2012		2011		2010
	Black-Scholes	Binomial	Black- Scholes	Binomial	Black-Scholes	Binomial
Risk-free interest rate (%)	0.87 – 1.17	0.08 – 2.04	1.69 – 1.93	0.04 – 3.03	1.50 – 3.20	0.02 – 3.66
Expected stock price volatility (%)	34.22 – 34.65	34.20 – 34.60	48.00	55.70 – 55.80	47.00 – 50.00	51.00 – 52.00
Expected dividend yield	—	—	—	—	—	—
Expected option life (in years)	6.25	—	6.25	—	6.25 – 7.00	—
Contractual life (in years)	—	14	—	14	—	13
Fair value	$19.25 – $29.80	$9.98 - $22.76	$16.33 – $17.85	$16.91 - $20.39	$11.95 – $13.24	$10.05 - $12.42

Summary of the weighted-average fair value of stock options granted, and the total intrinsic value of stock options exercised

		2012		2011		2010
Weighted-average fair value at date of grant		$	20.77	$	17.66	$	18.18
Intrinsic value of options exercised	(in thousands)	17,598		4,966		7,530
Fair value of options vested	(in thousands)	2,790		3,536		926

Summary of the activity of the entity's stock options

	Number of options		Weighted average exercise price		Weighted average contractual term (in years)	Aggregate intrinsic value (in thousands)
Outstanding at December 31, 2011	3,243,958		$	14.19	6.7	$	116,755
Granted	278,500		69.48
Exercised	(285,054	)	12.19
Forfeited	(179,095	)	28.35
Outstanding at December 31, 2012	3,058,309		17.69		6.11	$	211,072
Exercisable at December 31, 2012	2,235,923		$	11.59	5.52	$	167,885

Summary of information about stock options outstanding and exercisable

	Options outstanding				Options exercisable
Exercise price range	Number	Weighted average remaining contractual life	Weighted average exercise price		Number	Weighted average remaining contractual life	Weighted average exercise price
$0.00 – $10.00(a)	1,901,386	5.43	$	9.13	1,771,805	5.42	$	9.13
$10.01 – $20.00(a)	187,912	3.55	12.50		177,912	3.37	12.44
$20.01 – $30.00(a)	611,561	7.29	22.94		247,814	7.28	22.87
$30.01 – $40.00(a)	108,950	8.54	34.16		17,329	8.53	33.48
$50.01 – $60.00(a)	10,000	9.37	53.15		1,250	9.37	53.00
$60.01 – $70.00(a)	158,500	9.19	60.66		19,813	9.19	60.66
$80.01 – $90.00(a)	80,000	9.62	80.89		—	—	—
	3,058,309				2,235,923

(a)             These options contain market-based components as described above.  All other options are time-based awards.

Summary of the market prices for options to begin to vest

	Market Based Options
(in thousands, except share prices) Vesting price	Ordinary performance		Extraordinary performance
$150.00 – $160.00	—		3
$160.01 – $170.00	3		—
$180.01 – $190.00	—		45
Over $190.01	—		1
	3		49
Weighted average share price	$	80.89	$	61.00