Derivative and Hedging Instruments (Details-2) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Commodity Derivative Contracts [Member]
Offsetting Assets [Line Items]
Gross amounts	$ 1,433	$ 230
Gross amounts offset in balance sheet	(1,176)	(192)
Collateral posted against derivative positions	0	0
Net amount presented in balance sheet	257	38
Financial Transmission Rights [Member]
Offsetting Assets [Line Items]
Gross amounts	42	73
Gross amounts offset in balance sheet	0	0
Collateral posted against derivative positions	0	0
Net amount presented in balance sheet	$ 42	$ 73

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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