RESTRUCTURING ACCRUAL - Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		8 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				$ 1,300
Initiatives charged to expense	$ 0	$ 1,620		1,071	$ 1,620
Balance at the end of the period	400			400
2016 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				497
Initiatives charged to expense				531		$ 2,000
Adjustments for changes in estimate				(26)
Cash payments				(898)
Balance at the end of the period	104			104
Taqua Restructuring Incentive [Member]
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				602
Initiatives charged to expense			$ 1,800	615
Adjustments for changes in estimate				(49)
Cash payments				(855)
Balance at the end of the period	313			313
Employee Severance [Member] \| 2016 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				497
Initiatives charged to expense				405		1,900
Adjustments for changes in estimate				(26)
Cash payments				(876)
Balance at the end of the period	0			0
Employee Severance [Member] \| Taqua Restructuring Incentive [Member]
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				384
Initiatives charged to expense			1,200	245
Adjustments for changes in estimate				(49)
Cash payments				(580)
Balance at the end of the period	0			0
Employee Severance [Member] \| 2015 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				168
Initiatives charged to expense				0
Adjustments for changes in estimate				0
Cash payments				(168)
Balance at the end of the period	0			0
Facility Closing [Member] \| 2016 Restructuring [Member]
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				0
Initiatives charged to expense				126		$ 100
Adjustments for changes in estimate				0
Cash payments				(22)
Balance at the end of the period	104			104
Facility Closing [Member] \| Taqua Restructuring Incentive [Member]
Restructuring Reserve [Roll Forward]
Balance at the beginning of the period				218
Initiatives charged to expense			$ 600	370
Adjustments for changes in estimate				0
Cash payments				(275)
Balance at the end of the period	$ 313			$ 313

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