FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fair Value Measurement [Abstract]
Realized gain on sale of securities	$ 200
Proceeds from sale of marketable securities within rabbi trust	1,348	$ 0
Purchase of marketable securities within rabbi trust	(1,348)	0
Transfers in (out) between levels	0	$ 0
Fair value of total debt	116,900		$ 124,800
Carrying amount of long-term debt	114,800		122,700
Investments held in Rabbi Trust [Member]
Fair Value Measurement [Abstract]
Proceeds from sale of marketable securities within rabbi trust	1,300
Purchase of marketable securities within rabbi trust	(1,348)
Securities measured at fair value	1,300		1,500
Investments held in Rabbi Trust [Member] \| us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember
Fair Value Measurement [Abstract]
Gross unrealized gains associated with the investment held in the rabbi trust			200
Nonrecurring [Member]
Fair Value Measurement [Abstract]
Financial assets accounted at fair value	$ 0		$ 0

No definition available.

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The amount of the transfers of assets or liabilities measured on a recurring basis between different levels of the fair value hierarchy.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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No definition available.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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Amount of cash outflow for purchase of marketable security.

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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