DERIVATIVES AND RISK MANAGEMENT ACTIVITIES Table 3 - Impact of Derivatives on Earnings (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Derivative Instruments, Gain (Loss)
Gain (loss) to be reclassified during next 12 months, forward-starting interest rate swaps	$ (4,000)		$ (4,000)
Designated as Hedging Instruments \| Fair Value Hedges \| Commodity contracts \| Cost of product sales
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in income on derivative	(294)	$ (1,134)	(1,597)	$ 1,327
Gain (loss) recognized in income on hedged item	(221)	1,111	997	(1,036)
Gain (loss) recognized in income for ineffective portion	(515)	(23)	(600)	291
Designated as Hedging Instruments \| Cash Flow Hedges \| Interest rate swaps \| Other comprehensive income
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in other comprehensive income on derivative (effective portion)	3,540	(2,064)	26,067	(10,005)
Designated as Hedging Instruments \| Cash Flow Hedges \| Interest rate swaps \| Interest expense, net
Derivative Instruments, Gain (Loss)
Gain (loss) reclassified from AOCI into interest expense, net (effective portion)	(1,719)	(1,584)	(4,271)	(5,112)
Not Designated as Hedging Instruments \| Commodity contracts \| Cost of product sales
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in income on derivative	$ (209)	$ (132)	$ (439)	$ (218)

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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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).

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