FAIR VALUE MEASUREMENTS (Narrative) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($) item	Sep. 30, 2018 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of Rabbi Trusts established | item	2
Net gains (losses) of the Rabbi Trust investments	$ 2,843	$ (222)
Unrealized net gains (losses) of the Rabbi Trust investments	$ 2,879	$ (214)