STOCK-BASED COMPENSATION (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010
STOCK-BASED COMPENSATION [Abstract]
Total compensation expense related to stock options and restricted stock awards, before taxes	$ 3,300,000		$ 1,600,000		$ 5,600,000		$ 3,900,000
Total compensation expense related to stock options and restricted stock awards, net income	1,900,000		908,000		3,200,000		2,200,000
Cash proceeds from stock option exercises					2,900,000		1,500,000
Net tax benefit (provision) recognized in equity for stock compensation plans					474,000		(216,000)
Incentive shares available to be issued (in shares)	4,994,702				4,994,702
Stock Options [Abstract]
Stock options vesting period, minimum (in years)					3Y
Stock options vesting period, maximum (in years)					4Y
Contractual term of stock option grants, minimum period (in years)					7Y
Contractual term of stock option grants, maximum period (in years)					10Y
Share-based Compensation Arrangement by Share-based Payment Award, Unvested Options, Weighted Average Grant Date Fair Values [Abstract]
Fair value assumptions, method used	Black-Scholes option-pricing model		Black-Scholes option-pricing model		Black-Scholes option-pricing model		Black-Scholes option-pricing model
Expected term (in years)		[1]		[1]	4	[2]		[1]
Expected volatility		[1]		[1]	78.10%	[3]		[1]
Expected dividend yield		[1]		[1]	0.20%	[4]		[1]
Risk-free interest rate		[1]		[1]	1.60%	[5]		[1]
Restricted Stock [Abstract]
Total fair value of restricted stock awards vested	846,000		409,000		2,500,000		1,700,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding at beginning of period (in shares)					1,438,979
Granted (in shares)					8,654
Exercised (in shares)					(228,160)
Forfeited (in shares)					(79,463)
Outstanding at end of period (in shares)	1,140,010				1,140,010
Vested or expected to vest at end of period (in shares)	1,127,526				1,127,526
Exercisable at end of period (in shares)	946,474				946,474
Stock options, additional disclosures [Abstract]
Outstanding at beginning of period, weighted average exercise price (in dollars per share)					$ 24.21
Granted, weighted average exercise price (in dollars per share)	$ 23.11				$ 23.11
Exercised, weighted average exercise price (in dollars per share)	$ 12.68				$ 12.68
Forfeited, weighted average exercise price (in dollars per share)					$ 26.36
Outstanding at end of period, weighted average exercise price (in dollars per share)	$ 26.36				$ 26.36
Vested or expected to vest at end of period, weighted average exercise price (in dollars per share)	$ 26.45				$ 26.45
Exercisable at end of period, weighted average exercise price (in dollars per share)	$ 27.98				$ 27.98
Outstanding at end of period, weighted average remaining term (in years)	2.46				2.46
Vested or expected to vest at end of period, weighted average remaining term (in years)					2.44
Exercisable at end of period, weighted average remaining term (in years)					2.15
Outstanding at end of period, aggregate intrinsic value	1,633,000				1,633,000
Vested or expected to vest at end of period, aggregate intrinsic value	1,585,000				1,585,000
Exercisable at end of period, aggregate intrinsic value	1,155,000				1,155,000
Unvested options, outstanding [Roll Forward]
Unvested options at beginning of period, weighted average grant date fair value (in shares)					416,851
Granted, weighted average grant date fair value (in shares)					8,654
Vested, weighted average grant date fair value (in shares)					(225,582)
Forfeited, weighted average grant date fair value (in shares)					(6,387)
Unvested options at end of period, weighted average grant date fair value (in shares)	193,536				193,536
Share-based Compensation Arrangement by Share-based Payment Award, Unvested Options, Weighted Average Grant Date Fair Values [Abstract]
Unvested options at beginning of period (dollars per share)					$ 5.04
Granted (dollars per share)	$ 0	[1]	$ 0	[1]	$ 13.21	[1]	$ 0	[1]
Vested (dollars per share)					$ 5.60
Forfeited (dollars per share)					$ 4.69
Unvested options at end of period (dollars per share)	$ 4.76				$ 4.76
Weighted average grant date fair value of stock options granted during the period (in dollars per share)	$ 0	[1]	$ 0	[1]	$ 13.21	[1]	$ 0	[1]
Total intrinsic value of options exercised	855,000		359,000		2,052,000		636,000
Total fair value of options vested	119,000		404,000		1,263,000		2,076,000
Total unrecognized stock compensation expense	552,000				552,000
Weighted average period to recognize unrecognized compensation cost (in years)					1.7
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Unvested Options, Weighted Average Grant Date Fair Values [Abstract]
Total unrecognized stock compensation expense	$ 23,900,000				$ 23,900,000
Weighted average period to recognize unrecognized compensation cost (in years)					2.3
Restricted Stock [Abstract]
Restricted stock award requisite service period for shares to become fully vested, minimum (in years)					3Y
Restricted stock award requisite service period for shares to become fully vested, maximum (in years)					5Y
Outstanding unvested at beginning of period (in shares)					1,789,498
Granted (in shares)					487,934
Vested (in shares)					(114,318)
Forfeited (in shares)					(138,594)
Outstanding unvested at end of period (in shares)	2,024,520				2,024,520
Outstanding unvested at beginning of period, weighted average price (in dollars per share)					$ 17.09
Granted, weighted average price (in dollars per share)					$ 22.67		$ 16.90
Vested, weighted average price (in dollars per share)					$ 30.14
Forfeited, weighted average price (in dollars per share)	$ 18.01				$ 18.01

[1] The Company did not issue any stock options during the three months ended June 30, 2011 and the six months ended June 30, 2010

[2] The expected term (estimated period of time outstanding) of stock options granted was estimated using the historical exercise behavior of employees

[3] The expected volatility was based on historical volatility for a period equal to the stock option's expected term

[4] The expected dividend yield is based on the Company's prevailing dividend rate at the time of grant

[5] The risk-free rate is based on the U.S. Treasury strips in effect at the time of grant equal to the stock's options expected term.