The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Risk Management and Derivatives: Utilities (Details) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2022	Jun. 30, 2022 USD ($) MMBTU	Dec. 31, 2021 MMBTU
Derivative [Line Items]
Credit Risk Derivative Liabilities, at Fair Value \| $		$ 0.4
Natural Gas, Distribution \| Cash Flow Hedging
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		2,416,000
Natural Gas, Distribution \| Natural gas futures purchased
Derivative [Line Items]
Derivative, Remaining Maturity	3 months	9 months
Natural Gas, Distribution \| Natural gas futures purchased \| Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		100,000	590,000
Natural Gas, Distribution \| Natural gas options purchased, net
Derivative [Line Items]
Derivative, Remaining Maturity	3 months	9 months
Natural Gas, Distribution \| Natural gas options purchased, net \| Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		430,000	3,100,000
Natural Gas, Distribution \| Natural gas basis swaps purchased
Derivative [Line Items]
Derivative, Remaining Maturity	3 months	0 months
Natural Gas, Distribution \| Natural gas basis swaps purchased \| Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		0	870,000
Natural Gas, Distribution \| Natural gas over-the-counter swaps, net
Derivative [Line Items]
Derivative, Remaining Maturity	34 months	30 months
Natural Gas, Distribution \| Natural gas over-the-counter swaps, net \| Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		7,090,000	4,570,000
Natural Gas, Distribution \| Natural gas physical contracts, net
Derivative [Line Items]
Derivative, Remaining Maturity	24 months	18 months
Natural Gas, Distribution \| Natural gas physical contracts, net \| Long
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount		12,166,541	16,416,677