Derivative and Hedging Instruments (Details-2) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Commodity Derivative Contracts [Member]
Offsetting Assets [Line Items]
Gross amounts	$ 683	$ 806
Gross amounts offset in balance sheet	(190)	(632)
Collateral posted against derivative positions	0	0
Net amount presented in balance sheet	493	$ 174
Financial Transmission Rights [Member]
Offsetting Assets [Line Items]
Gross amounts	38
Gross amounts offset in balance sheet	0
Collateral posted against derivative positions	0
Net amount presented in balance sheet	$ 38

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

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