STOCK-BASED COMPENSATION (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
STOCK-BASED COMPENSATION [Abstract]
Total compensation expense related to stock options and restricted stock awards, before taxes	$ 3,800,000		$ 2,300,000		$ 9,300,000		$ 6,200,000
Total compensation expense related to stock options and restricted stock awards, net income	2,200,000		1,300,000		5,400,000		3,600,000
Cash proceeds from stock option exercises					3,200,000		1,900,000
Net tax benefit (provision) recognized in equity for stock compensation plans					546,000		(156,000)
Incentive shares available to be issued (in shares)	4,810,907				4,810,907
Stock options, additional disclosures [Abstract]
Outstanding at beginning of period (in shares)					1,438,979
Outstanding at beginning of period, weighted average exercise price (in dollars per share)					$ 24.21
Granted (in shares)					8,654
Granted, weighted average exercise price (in dollars per share)	$ 23.11				$ 23.11
Exercised (in shares)					(255,258)
Exercised, weighted average exercise price (in dollars per share)	$ 12.60				$ 12.60
Forfeited (in shares)					(90,309)
Forfeited, weighted average exercise price (in dollars per share)					$ 26.34
Outstanding at end of period (in shares)	1,102,066				1,102,066
Outstanding at end of period, weighted average exercise price (in dollars per share)	$ 26.72				$ 26.72
Outstanding at end of period, weighted average remaining term (in years)	2.22				2.22
Outstanding at end of period, aggregate intrinsic value	419,000				419,000
Vested or expected to vest at end of period (in shares)	1,089,954				1,089,954
Vested or expected to vest at end of period, weighted average exercise price (in dollars per share)	$ 26.81				$ 26.81
Vested or expected to vest at end of period, weighted average remaining term (in years)					2.20
Vested or expected to vest at end of period, aggregate intrinsic value	396,000				396,000
Exercisable at end of period (in shares)	912,255				912,255
Exercisable at end of period, weighted average exercise price (in dollars per share)	$ 28.45				$ 28.45
Exercisable at end of period, weighted average remaining term (in years)					1.90
Exercisable at end of period, aggregate intrinsic value	181,000				181,000
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)					(10,112)
Unvested options at end of period, weighted average grant date fair value (in shares)	189,811				189,811
Share-based Compensation Arrangement by Share-based Payment Award, Unvested Options, Weighted Average Grant Date Fair Values [Abstract]
Unvested options at beginning of period (per share)					$ 5.04
Granted (in dollars per share)	$ 0	[1]	$ 0	[1]	$ 13.21		$ 0	[1]
Vested (in dollars per share)					$ 5.60
Forfeited (in dollars per share)					$ 4.69
Unvested at end of period (in dollars per share)	$ 4.76				$ 4.76
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 (in hundredths)		[1]		[1]	78.10%	[3]		[1]
Expected dividend yield (in hundredths)		[1]		[1]	0.20%	[4]		[1]
Risk-free interest rate (in hundredths)		[1]		[1]	1.60%	[5]		[1]
Weighted average grant date fair value of stock options granted during the period (in dollars per share)	$ 0	[1]	$ 0	[1]	$ 13.21		$ 0	[1]
Total intrinsic value of options exercised	123,000		353,000		2,175,000		989,000
Total fair value of options vested	0		32,000		1,263,000		2,108,000
Stock Options [Member]
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
Restricted Stock [Abstract]
Total unrecognized stock compensation expense	361,000				361,000
Weighted average period to recognize unrecognized compensation cost (in years)					2.0
Restricted Stock [Member]
Restricted Stock [Abstract]
Outstanding unvested at beginning of period (in shares)					1,789,498
Granted (in shares)					704,970
Vested (in shares)					(198,510)
Forfeited (in shares)					(202,671)
Outstanding unvested at end of period (in shares)	2,093,287				2,093,287
Outstanding unvested at beginning of period, weighted average price (in dollars per share)					$ 17.09
Granted, weighted average price (in dollars per share)					$ 21.42		$ 16.82
Vested, weighted average price (in dollars per share)					$ 24.44
Forfeited, weighted average price (in dollars per share)	$ 17.76				$ 17.76
Outstanding unvested at end of period, weighted average price (in dollars per share)	$ 17.79				$ 17.79
Total fair value of restricted stock awards vested	1,500,000		533,000		4,000,000		2,200,000
Total unrecognized stock compensation expense	$ 23,400,000				$ 23,400,000
Weighted average period to recognize unrecognized compensation cost (in years)					2.0

[1] The Company did not issue any stock options during the three months ended September 30, 2011 and the nine months ended September 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 option's expected term.