DISCONTINUED OPERATIONS AND ASSETS HELD FOR SALE - Narrative (Details) $ in Thousands, £ in Millions	1 Months Ended			3 Months Ended		6 Months Ended		12 Months Ended
	May 31, 2015 USD ($)	Jan. 31, 2015 USD ($)	Jan. 31, 2015 GBP (£)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) facility
Income Statement Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Businesses sold, number of facilities | facility								5
Proceeds from sale of businesses						$ 0	$ 22,730	$ 31,000
Pre-tax gains (losses)								(17,000)
Impairment of assets held for sale					$ 41,000	0	40,813
Gain (loss) on sale of business						0	(13,498)
Net tax expense (benefit)					3,065		3,065	$ 3,000
Net sales				$ 0	23,000	0	57,300
Loss from discontinued operations, net of taxes				$ 0	(14,384)	$ 0	$ (41,616)
Downstream [Member]
Income Statement Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from sale of businesses	$ 19,000
Impairment of assets held for sale					40,000
Gain (loss) on sale of business					$ 14,000
Aviation Ground Support [Member]
Income Statement Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from sale of businesses		$ 4,000	£ 3