STOCK-BASED COMPENSATION (Details 2) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2015 USD ($) $ / shares shares
Time-based restricted stock awards
Shares
Outstanding at beginning of period (in shares) | shares	751,020
Granted (in shares) | shares	466,125
Vested (in shares) | shares	(218,363)
Forfeited (in shares) | shares	(57,278)
Outstanding at end of period (in shares) | shares	941,504
Weighted Average Price
Outstanding at beginning of period (in dollars per share)	$ 30.61
Granted (in dollars per share)	40.35
Vested (in dollars per share)	23.41
Forfeited (in dollars per share)	36.41
Outstanding at end of period (in dollars per share)	$ 36.75
Additional disclosures
Total unrecognized stock compensation expense | $	$ 25.6
Weighted average period to recognize unrecognized compensation cost	2 years 29 days
Performance-based restricted stock awards
Shares
Outstanding at beginning of period (in shares) | shares	518,553
Granted (in shares) | shares	149,284
Vested (in shares) | shares	(144,445)
Outstanding at end of period (in shares) | shares	523,392
Weighted Average Price
Outstanding at beginning of period (in dollars per share)	$ 29.64
Granted (in dollars per share)	39.95
Vested (in dollars per share)	22.05
Outstanding at end of period (in dollars per share)	$ 35.64
Additional disclosures
Total unrecognized stock compensation expense | $	$ 9.5
Weighted average period to recognize unrecognized compensation cost	1 year 10 months 17 days