Fair Value of Financial Assets and Liabilities (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Gross Notional Amounts of Commodity Forwards and Options

Gross notional amounts of commodity forwards and options:

(Amounts in Millions) (a)(b)	March 31, 2021	Dec. 31, 2020
Megawatt hours of electricity	22	17
Million British thermal units of natural gas	86	93

(a)Amounts are not reflective of net positions in the underlying commodities.

(b)Notional amounts for options are included on a gross basis, but are weighted for the probability of exercise.

Impact of Derivative Activity on Accumulated Other Comprehensive Loss, Regulatory Assets and Liabilities, and Income

	Pre-Tax (Gains) Losses Reclassified into Income During the Period from:					Pre-Tax Gains (Losses) Recognized During the Period in Income
(Millions of Dollars)	Accumulated Other Comprehensive Loss		Regulatory Assets and (Liabilities)
Three Months Ended March 31, 2021
Other derivative instruments
Commodity trading	$	—	$	—		$	1	(a)
Natural gas commodity	—		6		(b)	(6)		(b)
Total	$	—	$	6		$	(5)

	Pre-Tax (Gains) Losses Reclassified into Income During the Period from:					Pre-Tax Gains (Losses) Recognized During the Period in Income
(Millions of Dollars)	Accumulated Other Comprehensive Loss		Regulatory Assets and (Liabilities)
Three Months Ended March 31, 2020
Other derivative instruments
Commodity trading	$	—	$	—		$	(2)	(a)
Natural gas commodity	—		3		(b)	(3)		(b)
Total	$	—	$	3		$	(5)

(a)    Amounts are recorded to electric operating revenues. Portions of these gains and losses are subject to sharing with electric customers through margin-sharing mechanisms and deducted from gross revenue as appropriate.

(b)    Amounts for both the three months ended March 31, 2021 and 2020, included no settlement gains or losses on derivatives entered to mitigate natural gas price risk for electric generation recorded to electric fuel and purchased power, subject to cost-recovery mechanisms and reclassified to a regulatory asset, as appropriate. The derivative settlement losses for both the three months ended March 31, 2021 and 2020 relate to natural gas operations and were recorded to cost of natural gas sold and transported. These gains and losses are subject to cost-recovery mechanisms and reclassified out of income to a regulatory asset or liability, as appropriate.

Derivative Assets and Liabilities Measured at Fair Value on a Recurring Basis by Hierarchy Level

	March 31, 2021												Dec. 31, 2020
	Fair Value						Fair Value Total		Netting (a)		Total		Fair Value						Fair Value Total		Netting (a)		Total
(Millions of Dollars)	Level 1		Level 2		Level 3								Level 1		Level 2		Level 3
Current derivative assets
Other derivative instruments:
Commodity trading	$	3	$	99	$	1	$	103	$	(80)	$	23	$	1	$	41	$	1	$	43	$	(28)	$	15
Natural gas commodity	—		—		—		—		—		—		—		6		—		6		—		6
Total current derivative assets	$	3	$	99	$	1	$	103	$	(80)	$	23	$	1	$	47	$	1	$	49	$	(28)	$	21
Noncurrent derivative assets
Other derivative instruments:
Commodity trading	$	1	$	45	$	14	$	60	$	(38)	$	22	$	1	$	27	$	8	$	36	$	(20)	$	16
Total noncurrent derivative assets	$	1	$	45	$	14	$	60	$	(38)	$	22	$	1	$	27	$	8	$	36	$	(20)	$	16

	March 31, 2021												Dec. 31, 2020
	Fair Value						Fair Value Total		Netting (a)		Total		Fair Value						Fair Value Total		Netting (a)		Total
(Millions of Dollars)	Level 1		Level 2		Level 3								Level 1		Level 2		Level 3
Current derivative liabilities
Other derivative instruments:
Commodity trading	$	2	$	110	$	2	$	114	$	(85)	$	29	$	1	$	46	$	7	$	54	$	(33)	$	21
Natural gas commodity	—		—		—		—		—		—		—		6		—		6		—		6
Total current derivative liabilities	$	2	$	110	$	2	$	114	$	(85)	$	29	$	1	$	52	$	7	$	60	$	(33)	$	27
Noncurrent derivative liabilities
Other derivative instruments:
Commodity trading	$	—	$	39	$	51	$	90	$	(40)	$	50	$	1	$	24	$	46	$	71	$	(20)	$	51
Total noncurrent derivative assets	$	—	$	39	$	51	$	90	$	(40)	$	50	$	1	$	24	$	46	$	71	$	(20)	$	51

(a)PSCo nets derivative instruments and related collateral on its consolidated balance sheets when supported by a legally enforceable master netting agreement, and all derivative instruments and related collateral amounts were subject to master netting agreements at March 31, 2021 and Dec. 31, 2020. At both March 31, 2021 and Dec. 31, 2020, derivative assets and liabilities include no obligations to return cash collateral. At March 31, 2021 and Dec. 31, 2020, derivative assets and liabilities include rights to reclaim cash collateral of $7 million and $5 million, respectively. The counterparty netting amounts presented exclude settlement receivables and payables and non-derivative amounts that may be subject to the same master netting agreements.

Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation

Changes in Level 3 commodity derivatives:

	Three Months Ended March 31
(Millions of Dollars)	2021		2020
Balance at Jan. 1	$	(44)	$	(13)
Settlements	(1)		—
Net transactions recorded during the period:
Gains (losses) recognized in earnings (a)	7		(1)
Balance at March 31	$	(38)	$	(14)

(a)Level 3 gains recognized in earnings are subject to offsetting losses of derivative instruments categorized as level 1 and 2 in the income statement.

Carrying Amount and Fair Value of Long-term Debt

Other financial instruments for which the carrying amount did not equal fair value:

	March 31, 2021				Dec. 31, 2020
(Millions of Dollars)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Long-term debt, including current portion	$	6,463	$	7,066	$	5,724	$	7,040