Derivative and Hedging Instruments (Details-2) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Offsetting Assets [Line Items]
Collateral posted against derivative positions	$ (9,200)	$ 0
Commodity Derivative Contracts [Member]
Offsetting Assets [Line Items]
Gross amounts	13,985	806
Gross amounts offset in balance sheet	(375)	(632)
Collateral posted against derivative positions	(9,235)	0
Net amount presented in balance sheet	4,375	$ 174
Financial Transmission Rights [Member]
Offsetting Assets [Line Items]
Gross amounts	225
Gross amounts offset in balance sheet	0
Collateral posted against derivative positions	0
Net amount presented in balance sheet	$ 225

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

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