STOCK PLANS (Non-Vested Stock Option Activity) (Details) (Stock options, USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stock options
Nonvested stock options, Number of Options
Balance at beginning of year (in shares)	929,382
Granted (in shares)	412,980	459,263	491,010
Vested (in shares)	(470,243)
Forfeited (in shares)	(19,630)
Balance at end of year (in shares)	852,489	929,382
Nonvested stock options, Weighted Average Fair Value at Grant Date
Balance at beginning of year, weighted average fair value at grant date (in dollars per share)	$ 10.78
Granted, weighted average fair value at grant date (in dollars per share)	$ 15.87
Vested, weighted average fair value at grant date (in dollars per share)	$ 10.19
Forfeited, weighted average fair value at grant date (in dollars per share)	$ 19.60
Balance at end of year, weighted average fair value at grant date (in dollars per share)	$ 13.63	$ 10.78