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LONG-TERM DEBT - Schedule Of Cash Flow Hedges Related to Derivative Instruments On the Balance Sheet (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Derivatives, Fair Value [Line Items] |  |  |  |  |
Cash flow hedge derivatives, assets | $ 2,159 |  | $ 2,159 |  | $ 401
Cash flow hedge derivatives, liabilities | 326 |  | 326 |  | 123
Accumulated other comprehensive income | 863 | $ 15 | 1,503 | $ (263) |
Other current assets | Designated as Hedging Instrument | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Cash flow hedge derivatives, assets | 350 |  | 350 |  | 0
Other non-current assets | Designated as Hedging Instrument | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Cash flow hedge derivatives, assets | 1,809 |  | 1,809 |  | 401
Other accrued liabilities | Designated as Hedging Instrument | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Cash flow hedge derivatives, liabilities | 326 |  | 326 |  | 123
Other long-term liabilities | Designated as Hedging Instrument | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Cash flow hedge derivatives, liabilities | $ 0 |  | 0 |  | 0
Accumulated other comprehensive income | Designated as Hedging Instrument | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Accumulated other comprehensive income, interest rate swaps |  |  | 1,811 |  | 278
Accumulated other comprehensive income, interest rate swaps - tax provision |  |  | (525) |  | (112)
Accumulated other comprehensive income |  |  | $ 1,286 |  | $ 166

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- Definition Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 + Details
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