DERIVATIVE INSTRUMENTS - Offsetting assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivative assets
Gross amounts	$ 11,967	$ 8,178
Gross amounts offset	(3,730)	(3,053)
Net Amounts	8,237	5,125
Derivative liabilities
Gross amounts	18,252	17,439
Gross amounts offset	(3,730)	(3,053)
Net Amounts	$ 14,522	$ 14,386

Fair value of liability associated with 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.

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