EARNINGS (LOSS) PER COMMON SHARE - Anti-dilutive Securities (Details) - shares	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
EARNINGS (LOSS) PER COMMON SHARE
Total potentially dilutive securities	359,400	1,067,934
Stock Options
EARNINGS (LOSS) PER COMMON SHARE
Total potentially dilutive securities	207,700	660,539
Convertible Preferred D Shares
EARNINGS (LOSS) PER COMMON SHARE
Total potentially dilutive securities	151,700	170,200
Time Vesting Units
EARNINGS (LOSS) PER COMMON SHARE
Total potentially dilutive securities		188,531
Financial Performance Units
EARNINGS (LOSS) PER COMMON SHARE
Total potentially dilutive securities		24,014
Market Performance Units
EARNINGS (LOSS) PER COMMON SHARE
Total potentially dilutive securities		24,650