STOCK COMPENSATION PLANS (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock purchase plan
Compensation expense recognized	$ 13,500,000	$ 12,700,000	$ 13,500,000
Stock Options
Summary of stock option activity
Outstanding at beginning of year (in shares)	677,708
Exercised (in shares)	(91,540)
Forfeited (in shares)	(179,437)
Outstanding at end of year (in shares)	406,731	677,708
Vested or expected to vest at year-end (in shares)	406,731
Exercisable at year-end (in shares)	406,731
Outstanding at beginning of year, weighted average exercise price (in dollars per share)	$ 28.41
Exercised, weighted average exercise price (in dollars per share)	$ 18.35
Forfeited, weighted average exercise price (in dollars per share)	$ 37.36
Outstanding at end of year, weighted average exercise price (in dollars per share)	$ 26.72	$ 28.41
Vested or expected to vest at year-end, weighted average exercise price (in dollars per share)	$ 26.72
Exercisable at year-end, weighted average exercise price (in dollars per share)	$ 26.72
Outstanding at end of year, weighted average remaining term	9 months 29 days
Vested or expected to vest at year-end, weighted average remaining term	9 months 29 days
Exercisable at year-end, weighted average remaining term	9 months 29 days
Outstanding at end of year, aggregate intrinsic value	3,848,000
Vested or expected to vest at year-end, aggregate intrinsic value	3,848,000
Exercisable at year-end, aggregate intrinsic value	3,848,000
Summary of unvested stock option activity
Unvested options at beginning of year (in shares)	14,502
Vested (in shares)	(14,502)
Unvested options at ending of year (in shares)		14,502
Unvested options at beginning of year, weighted average grant date fair value (in dollars per share)	$ 3.00
Vested, weighted average grant date fair value (in dollars per share)	$ 3.00
Unvested options at ending of year, weighted average grant date fair value (in dollars per share)		$ 3.00
Fair value assumptions under the Black-Scholes option pricing model
Fair value assumptions, method used	Black-Scholes option-pricing model		Black-Scholes option-pricing model
Expected term			4 years	[1]
Expected volatility (as a percent)			78.10%	[2]
Expected dividend yield (as a percent)			0.20%	[3]
Risk-free interest rate (as a percent)			1.60%	[4]
Share based compensation plan, additional disclosures
Weighted average grant date fair value of stock options granted during the year (in dollars per share)			$ 13.21	[5]
Total intrinsic value of options exercised	926,000	978,000	2,650,000
Total fair value of options vested	363,000	3,717,000	1,274,000
Stock Options | Minimum
Stock Options
Vesting period	3 years
Contractual term of stock option grants	7 years
Stock Options | Maximum
Stock Options
Vesting period	4 years
Contractual term of stock option grants	10 years
Stock Purchase Plan
Stock purchase plan
Purchase price of shares in terms compared to market price per share (as a percent)	90.00%
Value of shares sold to employees under purchase plan	25,000
Compensation expense recognized	0
Common stock, shares authorized (in shares)	2,000,000
Shares sold to employees under purchase plan (in shares)	53,015	59,142
Stock Issued During Period, Value, Employee Stock Purchase Plan	$ 1,400,000	$ 1,200,000

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

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

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

[4] 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.

[5] The Company did not issue any stock options during the years ended December 31, 2013 and December 31, 2012.