FERC-authorized short-term debt through February 6, 2012

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Debt Instrument, Covenant Ratio

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Amount of allowance for credit loss on accounts receivable.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for letter of credit arrangements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Indebtedness divided by net capital.

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No definition available.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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No definition available.

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Amount of operating expense for purchased power of regulated operation.

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Balance Sheet Components (Details) $ in Millions	3 Months Ended
Balance Sheet Components (Details) $ in Millions	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Apr. 09, 2020 USD ($)
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Accounts Receivable, Allowance for Credit Loss	$ 20		$ 16
Unbilled Receivables, Current	86		97
Finite-Lived Intangible Assets, Accumulated Amortization	403		388
Amortization of Intangible Assets	15
Line of Credit Facility, Maximum Borrowing Capacity	$ 600
Debt Instrument, Covenant Description	65.00%
Ratio of Indebtedness to Net Capital	0.552
Short-term debt	$ 200		150	$ 150
Line of Credit Facility, Remaining Borrowing Capacity	500
Line of Credit Facility, Current Borrowing Capacity	220	$ 500
Letters of credit issued	75
Authorized Short-Term Debt	900
Long-term Debt, Current Maturities	20		$ 160
Proceeds from Issuance of Long-term Debt	0	119
Purchased power and fuel	169	153
Repayments of Long-term Debt	140	$ 98
Letter of Credit [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Short-term debt	$ 0