QUARTERLY FINANCIAL DATA (UNAUDITED) (NARRATIVE) (DETAILS) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loss on assets held-for-sale									$ 2,578
Interest Expense.									13,734	$ 7,943	$ 7,538
Taxes related to US tax reform	$ 62,400								$ 61,569		0
Benefit to Income Taxes Related to Restructuring Charges	1,900	$ 2,400	$ 1,500		$ 200	$ 1,300
Net Change in Valuation Allowance	600				400		$ 1,000	$ 100
Benefit to Income Taxes Related to Impairments	1,900				8,300	1,500
Benefit to Income Taxes Related to Dispositon of Assets			1,300
Expense to Income Taxes Related to Dispositon of Assets	400	1,300
Tax Adjustments, Settlements, and Unusual Provisions	300	(200)	700	$ (300)
Expense to Income Taxes Related to Uncertain Tax Position					400	$ 600	$ 700
Expense Related to Tax Rate Changes					$ 500
Excess tax benefit from equity-based awards	200	$ 1,000	$ 700	$ 300						$ 557	$ (823)
Connextions
Interest Expense.	5,250
Motif [Member]
Interest Expense.	$ 1,200