DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING - Schedule of gain or loss recognized on derivative financial instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Derivative instruments, gain (loss) recognized
Total interest expense in which the effects of cash flow hedges are recorded	$ 10,852	$ 9,329
Cash flow hedges \| Interest rate swaps
Derivative instruments, gain (loss) recognized
(Loss) gain recognized in Other comprehensive income on derivative financial instruments	(5,497)	3,537
Total interest expense in which the effects of cash flow hedges are recorded	10,852	9,329
Cash flow hedges \| Interest rate swaps \| Interest expense
Derivative instruments, gain (loss) recognized
Gain (loss) reclassified from Other comprehensive income to Interest expense	$ 61	$ (207)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Amount of the cost of borrowed funds accounted for as interest expense.

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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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