DERIVATIVE INSTRUMENTS - Offsetting assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivative assets
Gross Amounts	$ 8,178	$ 22,270
Gross Amounts Offset	(3,053)	(5,373)
Net Amounts	5,125	16,897
Derivative liabilities
Gross Amounts	17,439	20,949
Gross Amounts Offset	(3,053)	(5,373)
Net Amounts	$ 14,386	$ 15,576

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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