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BUSINESS ACQUISITIONS (Fair Value of Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ / shares in Units, $ in Thousands	Jul. 20, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Business Acquisition [Line Items]
Goodwill		$ 226,505	$ 225,450	$ 225,450
Aegis
Business Acquisition [Line Items]
Stock consideration (number of shares outstanding immediately prior the closing date)	16,226,392
Closing share price on July 20, 2018	$ 6.81
Total allocable purchase price	$ 110,502
Cash and cash equivalents	1,496
Other current assets	46,094
Property, plant and equipment, net	15,930
Identifiable intangible assets	28,960
Goodwill	64,337
Other non-current assets	3,204
Current liabilities	(22,540)
Non-current liabilities	(26,979)
Preliminary purchase price	$ 110,502