EMPLOYEE BENEFIT PLANS, STOCK OPTIONS BY EXERCISE PRICE RANGE (Details)	12 Months Ended
	Dec. 31, 2012
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	2,456,137
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	3 years 4 months 24 days
Vested Options, Amount ( in shares)	2,317,799
Vested Options, Weighted Average Contractual Years Remaining	3 years 1 month 6 days
Exercise Price $8.34 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	71,148
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	6 years 3 months 18 days
Vested Options, Amount ( in shares)	42,532
Vested Options, Weighted Average Contractual Years Remaining	7 years 3 months 18 days
Exercise Price $12.75 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	78,871
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	7 years 3 months 18 days
Vested Options, Amount ( in shares)	51,407
Vested Options, Weighted Average Contractual Years Remaining	8 years 3 months 18 days
Exercise Price $13.16 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	146,708
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	1 month 6 days
Vested Options, Amount ( in shares)	146,708
Vested Options, Weighted Average Contractual Years Remaining	1 year 1 month 6 days
Exercise Price $13.74 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	859,375
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	4 years 3 months 18 days
Vested Options, Amount ( in shares)	859,375
Vested Options, Weighted Average Contractual Years Remaining	5 years 3 months 18 days
Exercise Price $14.92 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	34,425
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	5 years 2 months 12 days
Vested Options, Amount ( in shares)	34,425
Vested Options, Weighted Average Contractual Years Remaining	6 years 2 months 12 days
Exercise Price $15.10 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	318,492
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	2 years 4 months 24 days
Vested Options, Amount ( in shares)	318,492
Vested Options, Weighted Average Contractual Years Remaining	3 years 4 months 24 days
Exercise Price $15.45 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	91,583
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	8 years 3 months 18 days
Vested Options, Amount ( in shares)	33,765
Vested Options, Weighted Average Contractual Years Remaining	9 years 3 months 18 days
Exercise Price $16.45 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	76,320
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	2 years 1 month 6 days
Vested Options, Amount ( in shares)	76,320
Vested Options, Weighted Average Contractual Years Remaining	3 years 1 month 6 days
Exercise Price $16.73 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	51,943
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	5 years 7 months 2 days
Vested Options, Amount ( in shares)	51,943
Vested Options, Weighted Average Contractual Years Remaining	6 years 7 months 2 days
Exercise Price $18.18 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	80,000
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	5 years 4 months 24 days
Vested Options, Amount ( in shares)	80,000
Vested Options, Weighted Average Contractual Years Remaining	6 years 4 months 24 days
Exercise Price $19.90 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	622,832
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	1 year 1 month 6 days
Vested Options, Amount ( in shares)	622,832
Vested Options, Weighted Average Contractual Years Remaining	2 years 1 month 6 days
Exercise Price $13.86 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, End of Period [Abstract]
Outstanding Options, Amount ( in shares)	24,440
Outstanding Options, Weighted Average Remaining Contractual Years Remaining	9 years 3 months 18 days
Vested Options, Amount ( in shares)	0
Vested Options, Weighted Average Contractual Years Remaining	0 years 0 months 0 days