BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Goodwill (Details) $ in Thousands		12 Months Ended
Oct. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Goodwill
Number of reporting units \| item		1
Goodwill impairment \| $	$ 0	$ 0	$ 0	$ 0

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Data Type:	xbrli:monetaryItemType
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