Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
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-Topic 815
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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Fixed interest rate related to the interest rate derivative.

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Nominal mass used to calculate payments on a derivative instrument.

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- Definition

Fair value as of the balance sheet date of all price risk derivative assets designated as cash flow hedging instruments.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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Fair value as of the balance sheet date of all price risk derivative liabilities designated as cash flow hedging instruments.

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DERIVATIVE FINANCIAL INSTRUMENTS (Details) lb in Millions	3 Months Ended	12 Months Ended
DERIVATIVE FINANCIAL INSTRUMENTS (Details) lb in Millions	Mar. 31, 2018 USD ($) lb	Dec. 31, 2017 USD ($) lb	Dec. 31, 2016 USD ($)	Jul. 02, 2016
Interest Rate Swap, Through December 2021
Derivative Financial Instruments
Unrealized gain (losses), net of tax, recorded in AOCI	$ 400,000
Interest Rate Swap, Through December 2021 \| Derivative contracts designated as hedging instruments
Derivative Financial Instruments
Aggregate notional amount	260,000,000
Long-term asset to recognize fair value of swaps			$ 600,000
Interest Rate Swap, Through December 2021 \| Derivative contracts designated as hedging instruments \| Term loan
Derivative Financial Instruments
Fixed rate (percentage)				2.535%
FX Forward Contracts
Derivative Financial Instruments
Aggregate notional amount	10,500,000	$ 9,000,000
Unrealized gain (losses), net of tax, recorded in AOCI	0	0
FX embedded derivatives \| Derivative contracts not designated as hedging instruments
Derivative Financial Instruments
Aggregate notional amount	800,000	1,100,000
Commodity Contracts
Derivative Financial Instruments
Unrealized gain (losses), net of tax, recorded in AOCI	(100,000)	800,000
Fair value of derivative contract - liability	$ 200,000
Fair value of derivative contract - current asset		$ 1,100,000
Commodity Contracts \| Derivative contracts designated as hedging instruments
Derivative Financial Instruments
Notional amount of commodity contracts (in pounds of copper) \| lb	3.4	3.6