Northern States Power 10-Q 27 Jul 23 2023 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2023	Jul. 27, 2023
Cover [Abstract]
Entity Registrant Name	NORTHERN STATES POWER CO /WI/
Entity Central Index Key	0000072909
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Amendment Flag	false
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-03140
Entity Incorporation, State or Country Code	WI
Entity Tax Identification Number	39-0508315
Entity Address, Address Line One	1414 West Hamilton Avenue
Entity Address, City or Town	Eau Claire
Entity Address, State or Province	WI
Entity Address, Postal Zip Code	54701
City Area Code	(715)
Local Phone Number	737-2625
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		933,000

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating revenues
Electric, non-affiliates	$ 185	$ 191	$ 389	$ 394
Electric, affiliates	51	52	101	99
Natural gas	24	35	101	113
Total operating revenues	260	278	591	606
Operating expenses
Electric fuel and purchased power, non-affiliates	3	4	7	8
Purchased power, affiliates	93	120	196	228
Cost of natural sold and transported	9	20	55	65
Operating and maintenance expenses	57	54	115	107
Conservation program expenses	4	3	7	6
Depreciation and amortization	42	40	83	78
Taxes (other than income taxes)	9	7	17	15
Total operating expenses	217	248	480	507
Operating income	43	30	111	99
Other income (expense), net	1	(1)	1	(1)
Allowance for funds used during construction — equity	2	1	4	3
Interest charges and financing costs
Interest charges and other financing costs	13	11	26	22
Allowance for funds used during construction — debt	(1)	0	(2)	(1)
Total interest charges and financing costs	12	11	24	21
Income before income taxes	34	19	92	80
Income tax expense	8	4	21	18
Net income	$ 26	$ 15	$ 71	$ 62

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating activities
Net income	$ 71	$ 62
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	84	78
Deferred income taxes	(6)	(1)
Allowance for equity funds used during construction	4	3
Provision for bad debts	2	2
Changes in operating assets and liabilities:
Accounts receivable	1	5
Accrued unbilled revenues	24	18
Inventories	10	(4)
Other current assets	9	(8)
Accounts payable	(17)	2
Net regulatory assets and liabilities	38	4
Other current liabilities	(2)	6
Pension and other employee benefit obligations	(2)	(1)
Other, net	4	(2)
Net cash provided by operating activities	212	158
Investing activities
Capital/construction expenditures	(209)	(155)
Net cash used in investing activities	(209)	(155)
Financing activities
Repayments of short-term borrowings, net	(47)	(83)
Borrowings under utility money pool arrangement	73	471
Repayments under utility money pool arrangement	(73)	(404)
Proceeds from long-term debt	124	0
Capital contributions from parent	46	51
Dividends paid to parent	(47)	(48)
Net cash provided by (used in) financing activities	76	(13)
Net change in cash, cash equivalents and restricted cash	79	(10)
Cash, cash equivalents and restricted cash at beginning of period	2	11
Cash, cash equivalents and restricted cash at end of period	81	1
Supplemental disclosure of cash flow information:
Cash paid for interest (net of amounts capitalized)	(22)	(20)
Cash paid for income taxes, net	(22)	(17)
Supplemental disclosure of non-cash investing and financing transactions:
Accrued property, plant and equipment additions	35	23
Inventory transfers to property, plant and equipment	5	2
Allowance for equity funds used during construction	$ 4	$ 3

CONSOLIDATED BALANCE SHEETS (UN

CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 81	$ 2
Accounts receivable, net	80	84
Accrued unbilled revenues	50	74
Other receivables	12	19
Inventories	24	39
Regulatory assets	32	44
Prepaid taxes	28	27
Prepayments and other	5	11
Total current assets	312	300
Property, Plant and Equipment, Net [Abstract]
Property, plant and equipment, net	3,055	2,914
Other assets
Regulatory assets	187	193
Other	3	3
Total other assets	190	196
Total assets	3,557	3,410
Current liabilities
Current portion of long-term debt	200	0
Short-term debt	0	47
Accounts payable	58	92
Dividends payable to parent	25	23
Regulatory liabilities	28	21
Taxes accrued	17	13
Accrued interest	12	12
Other	20	28
Total current liabilities	381	255
Deferred credits and other liabilities
Deferred income taxes	331	333
Deferred investment tax credits	5	5
Regulatory liabilities	415	383
Customer advances	24	23
Pension and employee benefit obligations	21	23
Other	43	43
Total deferred credits and other liabilities	839	810
Commitments and contingencies
Capitalization
Long-term debt	1,011	1,086
Common stock — 1,000,000 shares authorized of $100 par value; 933,000 shares outstanding at June 30, 2023 and Dec. 31, 2022, respectively	$ 93	$ 93
Common stock, shares authorized (in shares)	1,000,000	1,000,000
Common stock, par value (in dollars per share)	$ 100	$ 100
Common stock, shares outstanding (in shares)	933,000	933,000
Additional paid in capital	$ 806	$ 761
Retained earnings	427	405
Total common stockholder's equity	1,326	1,259
Total liabilities and equity	3,557	3,410
Accounts payable	58	92
Related Party
Current liabilities
Accounts payable	21	19
Accounts payable	$ 21	$ 19

CONSOLIDATED STATEMENTS OF COMM

CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($) $ in Millions	Total	Common stock	Additional Paid In Capital	Retained Earnings
Balance (in shares) at Dec. 31, 2021		933,000
Beginning Balance at Dec. 31, 2021	$ 1,103	$ 93	$ 642	$ 368
Increase (Decrease) in Stockholder's Equity
Net income	62
Common dividends declared to parent	(41)			(41)
Contribution of capital by parent	60		60
Balance (in shares) at Jun. 30, 2022		933,000
Ending Balance at Jun. 30, 2022	1,184	$ 93	702	389
Balance (in shares) at Mar. 31, 2022		933,000
Beginning Balance at Mar. 31, 2022	1,158	$ 93	672	393
Increase (Decrease) in Stockholder's Equity
Net income	15			15
Common dividends declared to parent	(19)			(19)
Contribution of capital by parent	30		30
Balance (in shares) at Jun. 30, 2022		933,000
Ending Balance at Jun. 30, 2022	$ 1,184	$ 93	702	389
Balance (in shares) at Dec. 31, 2022	933,000	933,000
Beginning Balance at Dec. 31, 2022	$ 1,259	$ 93	761	405
Increase (Decrease) in Stockholder's Equity
Net income	71
Common dividends declared to parent	(49)			(49)
Contribution of capital by parent	$ 45		45
Balance (in shares) at Jun. 30, 2023	933,000	933,000
Ending Balance at Jun. 30, 2023	$ 1,326	$ 93	806	427
Balance (in shares) at Mar. 31, 2023		933,000
Beginning Balance at Mar. 31, 2023	1,310	$ 93	791	426
Increase (Decrease) in Stockholder's Equity
Net income	26			26
Common dividends declared to parent	(25)			(25)
Contribution of capital by parent	$ 15		15
Balance (in shares) at Jun. 30, 2023	933,000	933,000
Ending Balance at Jun. 30, 2023	$ 1,326	$ 93	$ 806	$ 427

CONSOLIDATED STATEMENTS OF IN_2

CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Statement [Abstract]
Other income (expense), net	$ 1	$ (1)	$ 1	$ (1)

Management's Opinion

Management's Opinion	6 Months Ended
	Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Management's Opinion	In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments necessary to present fairly, in accordance with GAAP, the financial position of NSP-Wisconsin and its subsidiaries as of June 30, 2023 and Dec. 31, 2022; the results of NSP-Wisconsin's operations, including the components of net income, changes in stockholder's equity and comprehensive income for the three and six months ended June 30, 2023 and 2022; and NSP-Wisconsin's cash flows for the six months ended June 30, 2023 and 2022. All adjustments are of a normal, recurring nature, except as otherwise disclosed. Management has also evaluated the impact of events occurring after June 30, 2023 up to the date of issuance of these consolidated financial statements. These statements contain all necessary adjustments and disclosures resulting from that evaluation. The Dec. 31, 2022 balance sheet information has been derived from the audited 2022 consolidated financial statements included in the NSP-Wisconsin Annual Report on Form 10-K for the year ended Dec. 31, 2022. Notes to the consolidated financial statements have been prepared pursuant to the rules and regulations of the SEC for Quarterly Reports on Form 10-Q. Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP on an annual basis have been condensed or omitted pursuant to such rules and regulations. For further information, refer to the consolidated financial statements and notes thereto included in the NSP-Wisconsin Annual Report on Form 10-K for the year ended Dec. 31, 2022, filed with the SEC on Feb. 23, 2023. Due to the seasonality of NSP-Wisconsin’s electric and natural gas sales, interim results are not necessarily an appropriate base from which to project annual results.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	The significant accounting policies set forth in Note 1 to the consolidated financial statements in the NSP-Wisconsin Annual Report on Form 10-K for the year ended Dec. 31, 2022 appropriately represent, in all material respects, the current status of accounting policies and are incorporated herein by reference.

Accounting Pronouncements

Accounting Pronouncements	6 Months Ended
	Jun. 30, 2023
Accounting Standards Update and Change in Accounting Principle [Abstract]
Accounting Pronouncements	As of June 30, 2023, there was no material impact from the recent adoption of new accounting pronouncements, nor expected material impact from recently issued accounting pronouncements yet to be adopted, on NSP-Wisconsin's consolidated financial statements.

Selected Balance Sheet Data

Selected Balance Sheet Data	6 Months Ended
	Jun. 30, 2023
Balance Sheet Related Disclosures [Abstract]
Selected Balance Sheet Data	(Millions of dollars) June 30, 2023 Dec. 31, 2022 Accounts receivable, net Accounts receivable $ 88 $ 93 Less allowance for bad debts (8) (9) Accounts receivable, net $ 80 $ 84 (Millions of dollars) June 30, 2023 Dec. 31, 2022 Inventories Materials and supplies $ 10 $ 8 Fuel 11 11 Natural gas 3 20 Total inventories $ 24 $ 39 (Millions of dollars) June 30, 2023 Dec. 31, 2022 Property, plant and equipment, net Electric plant $ 3,708 $ 3,579 Natural gas plant 478 465 Common and other property 270 260 Construction work in progress 210 174 Total property, plant and equipment 4,666 4,478 Less accumulated depreciation (1,611) (1,564) Property, plant and equipment, net $ 3,055 $ 2,914

Borrowings and Other Financing

Borrowings and Other Financing Instruments	6 Months Ended
	Jun. 30, 2023
Debt Disclosure [Abstract]
Borrowings and Other Financing Instruments	Short-Term Borrowings NSP-Wisconsin meets its short-term liquidity requirements primarily through the issuance of commercial paper and borrowings under its credit facility and the money pool. Money Pool — Xcel Energy Inc. and its utility subsidiaries have established a money pool arrangement that allows for short-term investments in and borrowings between the utility subsidiaries. Xcel Energy Inc. may make investments in the utility subsidiaries at market-based interest rates; however, the money pool arrangement does not allow the utility subsidiaries to make investments in Xcel Energy Inc. Money pool borrowings: (Amounts in Millions, Except Interest Rates) Three Months Ended June 30, 2023 Year Ended Dec. 31, 2022 Borrowing limit $ 150 $ 150 Amount outstanding at period end — — Average amount outstanding 18 25 Maximum amount outstanding 43 81 Weighted average interest rate, computed on a daily basis 4.84 % 1.10 % Weighted average interest rate at period end N/A N/A Commercial Paper — Commercial paper outstanding: (Amounts in Millions, Except Interest Rates) Three Months Ended June 30, 2023 Year Ended Dec. 31, 2022 Borrowing limit $ 150 $ 150 Amount outstanding at period end — 47 Average amount outstanding 4 18 Maximum amount outstanding 30 123 Weighted average interest rate, computed on a daily basis 5.01 % 1.03 % Weighted average interest rate at period end N/A 4.55 Letters of Credit — NSP-Wisconsin uses letters of credit, generally with terms of one year, to provide financial guarantees for certain obligations. At both June 30, 2023 and Dec. 31, 2022, there we re no l etters of credit outstanding under the credit facility. Revolving Credit Facility — In order to issue its commercial paper, NSP-Wisconsin must have a revolving credit facility equal to or greater than the commercial paper borrowing limit and cannot issue commercial paper exceeding available capacity under this credit facility. The credit facility provides short-term financing in the form of notes payable to banks, letters of credit and back-up support for commercial paper borrowings. NSP-Wisconsin has the right to request an extension of the revolving credit facility termination date for an additional one-year period. All extension requests are subject to majority bank group approval. As of June 30, 2023, NSP-Wisconsin had the following committed revolving credit facility available (in millions of dollars): Credit Facility (a) Outstanding (b) Available $ 150 $ — $ 150 (a) Expires in September 2027. (b) Includes outstanding commercial paper. All credit facility ban k borrowings, outstanding letters of credit and outstanding commercial paper reduce the available capacity under the credit facility. NSP-Wisconsin had no direct advances on the credit facility outstanding at June 30, 2023 and Dec. 31, 2022. Other Short-Term Borrowings — Clearwater Investments, Inc., a NSP-Wisconsin subsidiary, had an immaterial note payable to Xcel Energy Inc. as of June 30, 2023 and Dec. 31, 2022, respectively. Long-Term Borrowings and Other Financing Instruments During the six months ended June 30, 2023, NSP-Wisconsin issued $125 million of 5.30% private placement first mortgage bonds due June 15, 2053.

Revenues

Revenues	6 Months Ended
	Jun. 30, 2023
Revenue from Contract with Customer [Abstract]
Revenues	Revenue is classified by the type of goods/services rendered and market/customer type. NSP-Wisconsin’s operating revenues consisted of the following: Three Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 68 $ 13 $ 81 C&I 122 9 131 Other 2 — 2 Total retail 192 22 214 Interchange and other 41 — 41 Total revenue from contracts with customers 233 22 255 Alternative revenue and other 3 2 5 Total revenues $ 236 $ 24 $ 260 Three Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 67 $ 18 $ 85 C&I 119 15 134 Other 2 — 2 Total retail 188 33 221 Interchange and other 53 1 54 Total revenue from contracts with customers 241 34 275 Alternative revenue and other 2 1 3 Total revenues $ 243 $ 35 $ 278 Six Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 150 $ 54 $ 204 C&I 242 43 285 Other 4 — 4 Total retail 396 97 493 Interchange and other 88 1 89 Total revenue from contracts with customers 484 98 582 Alternative revenue and other 6 3 9 Total revenues $ 490 $ 101 $ 591 Six Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 148 $ 60 $ 208 C&I 235 49 284 Other 4 — 4 Total retail 387 109 496 Interchange and other 101 2 103 Total revenue from contracts with customers 488 111 599 Alternative revenue and other 5 2 7 Total revenues $ 493 $ 113 $ 606

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	6. Income Taxes Reconciliation between the statutory rate and effective tax rate: Six Months Ended June 30 2023 2022 Federal statutory rate 21.0 % 21.0 % State tax (net of federal tax effect) 6.2 6.2 Decreases: Plant regulatory differences (a) (3.5) (4.0) Other (net) (0.9) (0.7) Effective income tax rate 22.8 % 22.5 %

Fair Value of Financial Assets

Fair Value of Financial Assets and Liabilities	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value of Financial Assets and Liabilities	7. Fair Value of Financial Assets and Liabilities Fair Value Measurements Accounting guidance for fair value measurements and disclosures provides a hierarchical framework for disclosing the observability of the inputs utilized in measuring assets and liabilities at fair value. • Level 1 — Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. The types of assets and liabilities included in Level 1 are actively traded instruments with observable actual trading prices. • Level 2 — Pricing inputs are other than actual trading prices in active markets, but are either directly or indirectly observable as of the reporting date. The types of assets and liabilities included in Level 2 are typically either comparable to actively traded securities or contracts or priced with models using highly observable inputs. • Level 3 — Significant inputs to pricing have little or no observability as of the reporting date. The types of assets and liabilities included in Level 3 include those valued with models requiring significant judgment or estimation. Specific valuation methods include: Commodity Derivatives — Methods used to measure the fair value of commodity derivative forwards and options utilize forward prices and volatilities, as well as pricing adjustments for specific delivery locations, and are generally assigned a Level 2 classification. When contracts relate to inactive delivery locations or extend to periods beyond those readily observable on active exchanges, the significance of the use of less observable inputs on a valuation is evaluated, and may result in Level 3 classification. Derivative Activities and Fair Value Measurements NSP-Wisconsin enters into derivative instruments, including forward contracts, futures, swaps and options, to manage risk in connection with changes in utility commodity prices. Commodity Derivatives — NSP-Wisconsin enters into derivative instruments to manage variability of future cash flows from changes in commodity prices in its electric and natural gas operations. This could include the purchase or sale of natural gas to generate electric energy and natural gas for resale. As of June 30, 2023, NSP-Wisconsin had no commodity contracts designated as cash flow hedges. Consideration of Credit Risk and Concentrations — NSP-Wisconsin continuously monitors the creditworthiness of counterparties to its interest rate derivatives and commodity derivative contracts prior to settlement, and assesses each counterparty’s ability to perform on the transactions set forth in the contracts. Impact of credit risk was immaterial to the fair value of unsettled commodity derivatives presented on the consolidated balance sheets. Recurring Derivative Fair Value Measurements Impact of derivative activity: Changes in the fair value of natural gas commodity derivatives resulted in immaterial net losses and gains for the three and six months ended June 30, 2023 and 2022, which were recognized as regulatory assets and liabilities. The classification as a regulatory asset or liability is based on commission approved regulatory recovery mechanisms. During the three and six months ended June 30, 2023 and 2022, there were immaterial natural gas commodity derivatives settlement losses and gains. During the three and six months ended June 30, 2023 and 2022, immaterial pre-tax losses were recognized during the period in income related to option premium amortization. NSP-Wisconsin had immaterial outstanding derivative assets or liabilities measured at fair value as of June 30, 2023 and Dec. 31, 2022. Fair Value of Long-Term Debt As of June 30, 2023, other financial instruments for which the carrying amount did not equal fair value: June 30, 2023 Dec. 31, 2022 (Millions of Dollars) Carrying Amount Fair Value Carrying Amount Fair Value Long-term debt, including current portion $ 1,211 $ 1,107 $ 1,086 $ 980 Fair value of NSP-Wisconsin’s long-term debt is estimated based on recent trades and observable spreads from benchmark interest rates for similar securities. Fair value estimates are based on information available to management as of June 30, 2023 and Dec. 31, 2022, and given the observability of the inputs, fair values presented for long-term debt were assigned as Level 2.

Benefit Plans and Other Postret

Benefit Plans and Other Postretirement Benefits	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Benefit Plans and Other Postretirement Benefits	Components of Net Periodic Benefit Cost Three Months Ended June 30 2023 2022 (Millions of Dollars) Pension Benefits Service cost $ 1 $ 1 Interest cost (a) 2 1 Expected return on plan assets (a) (2) (2) Amortization of net loss (a) — 1 Net benefit cost recognized for financial reporting $ 1 $ 1 Six Months Ended June 30 2023 2022 (Millions of Dollars) Pension Benefits Service cost $ 2 $ 2 Interest cost (a) 3 2 Expected return on plan assets (a) (4) (4) Amortization of net loss (a) 1 2 Net benefit cost recognized for financial reporting $ 2 $ 2 (a) The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Legal NSP-Wisconsin is involved in various litigation matters in the ordinary course of business. The assessment of whether a loss is probable or is a reasonable possibility, and whether the loss or a range of loss is estimable, often involves a series of complex judgments about future events. Management maintains accruals for losses probable of being incurred and subject to reasonable estimation. Management is sometimes unable to estimate an amount or range of a reasonably possible loss in certain situations, including but not limited to when (1) the damages sought are indeterminate, (2) the proceedings are in the early stages, or (3) the matters involve novel or unsettled legal theories. In such cases, there is considerable uncertainty regarding the timing or ultimate resolution, including a possible eventual loss. For current proceedings not specifically reported herein, management does not anticipate that the ultimate liabilities, if any, would have a material effect on NSP-Wisconsin’s consolidated financial statements. Legal fees are generally expensed as incurred. Gas Trading Litigation — e prime is a wholly owned subsidiary of Xcel Energy. e prime was in the business of natural gas trading and marketing but has not engaged in natural gas trading or marketing activities since 2003. Multiple lawsuits involving multiple plaintiffs seeking monetary damages were commenced against e prime and its affiliates, including Xcel Energy, between 2003 and 2009 alleging fraud and anticompetitive activities in conspiring to restrain the trade of natural gas and manipulate natural gas prices. Cases were all consolidated in the U.S. District Court in Nevada. One case remains active which includes a multi-district litigation matter consisting of a Wisconsin purported class (Arandell Corp.). The Court issued a ruling in June 2022 granting plaintiffs’ class certification. In April 2023, the Seventh Circuit Court of Appeals heard the defendants’ appeal challenging whether the district court properly assessed class certification. A decision relating to class certification is expected later this year. Xcel Energy considers the reasonably possible loss associated with this litigation to be immaterial. Rate Matters NSP-Wisconsin is involved in various regulatory proceedings arising in the ordinary course of business. Until resolution, typically in the form of a rate order, uncertainties may exist regarding the ultimate rate treatment for certain activities and transactions. Amounts have been recognized for probable and reasonably estimable losses that may result. Unless otherwise disclosed, any reasonably possible range of loss in excess of any recognized amount is not expected to have a material effect on the financial statements. MISO ROE Complaints — In November 2013 and February 2015, customer groups filed two ROE complaints against MISO TOs, which includes NSP-Minnesota and NSP-Wisconsin. The first complaint requested a reduction in base ROE transmission formula rates from 12.38% to 9.15% for the time period of Nov. 12, 2013 to Feb. 11, 2015, and removal of ROE adders (including those for RTO membership). The second complaint requested, for a subsequent time period, a base ROE reduction from 12.38% to 8.67%. The FERC subsequently issued various related orders (including Opinion Nos. 569, 569A and 569B) related to ROE methodology/calculations and timing. NSP-Minnesota has processed refunds to customers for applicable complaint periods based on the ROE in the most recent applicable opinions on behalf of the NSP System. The MISO TOs and various other parties have filed petitions for review of the FERC’s most recent applicable opinions at the D.C. Circuit. In August 2022, the D.C. Circuit ruled that FERC had not adequately supported its conclusions, vacated FERC’s related orders, and remanded the issue back to FERC for further proceedings, which remain pending. Additional exposure, if any, related to this matter is expected to be immaterial. Environmental MGP, Landfill and Disposal Sites NSP-Wisconsin is investigating, remediating or performing post-closure actions at one MGP, landfill or other disposal sites across its service territories. NSP-Wisconsin has recognized its best estimate of costs/liabilities from final resolution of these issues, however, the outcome and timing are unknown. In addition, there may be insurance recovery and/or recovery from other potentially responsible parties, offsetting a portion of costs incurred. Environmental Requirements — Water and Waste Federal Clean Water Act Section 316(b) — The Federal Clean Water Act requires the EPA to regulate cooling water intake structures to assure they reflect the best technology available for minimizing impingement and entrainment of aquatic species. NSP-Wisconsin estimates capital expenditures of approximately $5 million may be required to comply with the requirements. NSP-Wisconsin believes two plants could be required to make improvements to reduce impingement and entrainment. NSP-Wisconsin anticipates these costs will be recoverable through regulatory mechanisms. Environmental Requirements — Air

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2023
Segment Reporting [Abstract]
Segment Information	NSP-Wisconsin evaluates performance based on profit or loss generated from the product or service provided. These segments are managed separately because the revenue streams are dependent upon regulated rate recovery, which is separately determined for each segment. NSP-Wisconsin has the following reportable segments: • Regulated Electric — The regulated electric utility segment generates electricity, which is transmitted and distributed in Wisconsin and Michigan. • Regulated Natural Gas — The regulated natural gas utility segment purchases, transports, stores and distributes natural gas in portions of Wisconsin and Michigan. Asset and capital expenditure information is not provided for NSP-Wisconsin's reportable segments. As an integrated electric and natural gas utility, NSP-Wisconsin operates significant assets that are not dedicated to a specific business segment. Reporting assets and capital expenditures by business segment would require arbitrary and potentially misleading allocations, which may not necessarily reflect the assets that would be required for the operation of the business segments on a stand-alone basis. Certain costs, such as common depreciation, common O&M expenses and interest expense are allocated based on cost causation allocators across each segment. In addition, a general allocator is used for certain general and administrative expenses, including office supplies, rent, property insurance and general advertising. NSP-Wisconsin's segment information: Three Months Ended June 30 (Millions of Dollars) 2023 2022 Regulated Electric Total revenues (a) $ 236 $ 243 Net income 30 15 Regulated Natural Gas Total revenues $ 24 $ 35 Net loss (3) (1) All Other Net (loss) income $ (1) $ 1 Consolidated Total Total operating revenues $ 260 $ 278 Net income 26 15 (a) Total revenues include $51 million and $52 million of affiliate electric revenue for the three months ended June 30, 2023 and 2022, respectively. Six Months Ended June 30 (Millions of Dollars) 2023 2022 Regulated Electric Total revenues (a) $ 490 $ 493 Net income 63 47 Regulated Natural Gas Operating revenues $ 101 $ 113 Intersegment revenue 1 — Total revenues $ 102 $ 113 Net income 8 14 All Other Net income $ — $ 1 Consolidated Total Operating revenues (a) $ 592 $ 606 Reconciling eliminations (1) — Total operating revenues $ 591 $ 606 Net income 71 62

Selected Balance Sheet Data (Ta

Selected Balance Sheet Data (Tables)	6 Months Ended
	Jun. 30, 2023
Balance Sheet Related Disclosures [Abstract]
Accounts Receivable, Net	(Millions of dollars) June 30, 2023 Dec. 31, 2022 Accounts receivable, net Accounts receivable $ 88 $ 93 Less allowance for bad debts (8) (9) Accounts receivable, net $ 80 $ 84
Inventories	(Millions of dollars) June 30, 2023 Dec. 31, 2022 Inventories Materials and supplies $ 10 $ 8 Fuel 11 11 Natural gas 3 20 Total inventories $ 24 $ 39
Property, Plant and Equipment, Net	(Millions of dollars) June 30, 2023 Dec. 31, 2022 Property, plant and equipment, net Electric plant $ 3,708 $ 3,579 Natural gas plant 478 465 Common and other property 270 260 Construction work in progress 210 174 Total property, plant and equipment 4,666 4,478 Less accumulated depreciation (1,611) (1,564) Property, plant and equipment, net $ 3,055 $ 2,914

Borrowings and Other Financin_2

Borrowings and Other Financing Instruments (Tables)	6 Months Ended
	Jun. 30, 2023
Borrowings and Other Financing Instruments [Abstract]
Credit Facilities	As of June 30, 2023, NSP-Wisconsin had the following committed revolving credit facility available (in millions of dollars): Credit Facility (a) Outstanding (b) Available $ 150 $ — $ 150 (a) Expires in September 2027. (b) Includes outstanding commercial paper.
Money Pool
Borrowings and Other Financing Instruments [Abstract]
Short-Term Borrowings	Money pool borrowings: (Amounts in Millions, Except Interest Rates) Three Months Ended June 30, 2023 Year Ended Dec. 31, 2022 Borrowing limit $ 150 $ 150 Amount outstanding at period end — — Average amount outstanding 18 25 Maximum amount outstanding 43 81 Weighted average interest rate, computed on a daily basis 4.84 % 1.10 % Weighted average interest rate at period end N/A N/A
Commercial Paper
Borrowings and Other Financing Instruments [Abstract]
Short-Term Borrowings	Commercial paper outstanding: (Amounts in Millions, Except Interest Rates) Three Months Ended June 30, 2023 Year Ended Dec. 31, 2022 Borrowing limit $ 150 $ 150 Amount outstanding at period end — 47 Average amount outstanding 4 18 Maximum amount outstanding 30 123 Weighted average interest rate, computed on a daily basis 5.01 % 1.03 % Weighted average interest rate at period end N/A 4.55

Revenues (Tables)

Revenues (Tables)	6 Months Ended
	Jun. 30, 2023
Revenue from Contract with Customer [Abstract]
Disaggregation of revenue	NSP-Wisconsin’s operating revenues consisted of the following: Three Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 68 $ 13 $ 81 C&I 122 9 131 Other 2 — 2 Total retail 192 22 214 Interchange and other 41 — 41 Total revenue from contracts with customers 233 22 255 Alternative revenue and other 3 2 5 Total revenues $ 236 $ 24 $ 260 Three Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 67 $ 18 $ 85 C&I 119 15 134 Other 2 — 2 Total retail 188 33 221 Interchange and other 53 1 54 Total revenue from contracts with customers 241 34 275 Alternative revenue and other 2 1 3 Total revenues $ 243 $ 35 $ 278 Six Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 150 $ 54 $ 204 C&I 242 43 285 Other 4 — 4 Total retail 396 97 493 Interchange and other 88 1 89 Total revenue from contracts with customers 484 98 582 Alternative revenue and other 6 3 9 Total revenues $ 490 $ 101 $ 591 Six Months Ended (Millions of Dollars) Electric Natural Gas Total Major revenue types Revenue from contracts with customers: Residential $ 148 $ 60 $ 208 C&I 235 49 284 Other 4 — 4 Total retail 387 109 496 Interchange and other 101 2 103 Total revenue from contracts with customers 488 111 599 Alternative revenue and other 5 2 7 Total revenues $ 493 $ 113 $ 606

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	Reconciliation between the statutory rate and effective tax rate: Six Months Ended June 30 2023 2022 Federal statutory rate 21.0 % 21.0 % State tax (net of federal tax effect) 6.2 6.2 Decreases: Plant regulatory differences (a) (3.5) (4.0) Other (net) (0.9) (0.7) Effective income tax rate 22.8 % 22.5 %

Fair Value of Financial Asset_2

Fair Value of Financial Assets and Liabilities (Tables)	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Derivative Assets and Liabilities Measured at Fair Value on a Recurring Basis by Hierarchy Level	Recurring Derivative Fair Value Measurements Impact of derivative activity: Changes in the fair value of natural gas commodity derivatives resulted in immaterial net losses and gains for the three and six months ended June 30, 2023 and 2022, which were recognized as regulatory assets and liabilities. The classification as a regulatory asset or liability is based on commission approved regulatory recovery mechanisms. During the three and six months ended June 30, 2023 and 2022, there were immaterial natural gas commodity derivatives settlement losses and gains. During the three and six months ended June 30, 2023 and 2022, immaterial pre-tax losses were recognized during the period in income related to option premium amortization. NSP-Wisconsin had immaterial outstanding derivative assets or liabilities measured at fair value as of June 30, 2023 and Dec. 31, 2022.
Carrying Amount and Fair Value of Long-term Debt	June 30, 2023 Dec. 31, 2022 (Millions of Dollars) Carrying Amount Fair Value Carrying Amount Fair Value Long-term debt, including current portion $ 1,211 $ 1,107 $ 1,086 $ 980

Benefit Plans and Other Postr_2

Benefit Plans and Other Postretirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Components of Net Periodic Benefit Cost	Components of Net Periodic Benefit Cost Three Months Ended June 30 2023 2022 (Millions of Dollars) Pension Benefits Service cost $ 1 $ 1 Interest cost (a) 2 1 Expected return on plan assets (a) (2) (2) Amortization of net loss (a) — 1 Net benefit cost recognized for financial reporting $ 1 $ 1 Six Months Ended June 30 2023 2022 (Millions of Dollars) Pension Benefits Service cost $ 2 $ 2 Interest cost (a) 3 2 Expected return on plan assets (a) (4) (4) Amortization of net loss (a) 1 2 Net benefit cost recognized for financial reporting $ 2 $ 2 (a) The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset. In January 2023, contributions totaling $50 million were made across Xcel Energy’s pension plans, of which $4 million was attributable to NSP-Wisconsin. Xcel Energy does not expect additional pension contributions during 2023.	[1]
[1]The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.

Segment Reporting (Tables)

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2023
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	NSP-Wisconsin's segment information: Three Months Ended June 30 (Millions of Dollars) 2023 2022 Regulated Electric Total revenues (a) $ 236 $ 243 Net income 30 15 Regulated Natural Gas Total revenues $ 24 $ 35 Net loss (3) (1) All Other Net (loss) income $ (1) $ 1 Consolidated Total Total operating revenues $ 260 $ 278 Net income 26 15 (a) Total revenues include $51 million and $52 million of affiliate electric revenue for the three months ended June 30, 2023 and 2022, respectively. Six Months Ended June 30 (Millions of Dollars) 2023 2022 Regulated Electric Total revenues (a) $ 490 $ 493 Net income 63 47 Regulated Natural Gas Operating revenues $ 101 $ 113 Intersegment revenue 1 — Total revenues $ 102 $ 113 Net income 8 14 All Other Net income $ — $ 1 Consolidated Total Operating revenues (a) $ 592 $ 606 Reconciling eliminations (1) — Total operating revenues $ 591 $ 606 Net income 71 62

Selected Balance Sheet Data - A

Selected Balance Sheet Data - Accounts Receivable (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Accounts Receivable, Net
Accounts receivable	$ 88	$ 93
Less allowance for bad debts	(8)	(9)
Accounts receivable, net	$ 80	$ 84

Selected Balance Sheet Data - I

Selected Balance Sheet Data - Inventories (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Inventory [Line Items]
Total Inventories	$ 24	$ 39
Materials and supplies
Inventory [Line Items]
Inventories	10	8
Fuel
Inventory [Line Items]
Inventories	11	11
Natural gas
Inventory [Line Items]
Inventories	$ 3	$ 20

Selected Balance Sheet Data - P

Selected Balance Sheet Data - Property, Plant and Equipment (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Public Utility, Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 4,666	$ 4,478
Less accumulated depreciation	(1,611)	(1,564)
Property, plant and equipment, net	3,055	2,914
Electric plant
Public Utility, Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,708	3,579
Natural gas plant
Public Utility, Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	478	465
Common and other property
Public Utility, Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	270	260
Construction work in progress
Public Utility, Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 210	$ 174

Borrowings and Other Financin_3

Borrowings and Other Financing Instruments, Commercial Paper (Details) - USD ($)		3 Months Ended	12 Months Ended
		Jun. 30, 2023	Dec. 31, 2022
Short-term Debt [Line Items]
Amount outstanding at period end		$ 0	$ 47,000,000
Credit Facility
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	[1]	150,000,000
Long-term Line of Credit		0	0
Commercial Paper
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		150,000,000	150,000,000
Amount outstanding at period end		0	47,000,000
Average amount outstanding		4,000,000	18,000,000
Maximum amount outstanding		$ 30,000,000	$ 123,000,000
Weighted average interest rate, computed on a daily basis		5.01%	1.03%
Weighted average interest rate at period end			4.55%
Money Pool
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 150,000,000	$ 150,000,000
Amount outstanding at period end		0	0
Average amount outstanding		18,000,000	25,000,000
Maximum amount outstanding		$ 43,000,000	$ 81,000,000
Weighted average interest rate, computed on a daily basis		4.84%	1.10%
[1]Expires in September 2027.

Borrowings and Other Financin_4

Borrowings and Other Financing Instruments, Letters of Credit (Details) - USD ($)	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Line of Credit Facility [Line Items]
Line of Credit Facility, Expiration Period	1 year
Amount outstanding at period end	$ 0	$ 47,000,000
Credit Facility
Line of Credit Facility [Line Items]
Long-term Line of Credit	$ 0	$ 0

Borrowings and Other Financin_5

Borrowings and Other Financing Instruments, Credit Facility (Details) - USD ($)		Jun. 30, 2023	Dec. 31, 2022
Payable to Affiliates
Line of Credit Facility [Line Items]
Notes Payable, Current		$ 0	$ 0
Credit Facility
Line of Credit Facility [Line Items]
Credit Facility	[1]	150,000,000
Outstanding	[2]	0
Available		150,000,000
Direct advances on the credit facility outstanding		$ 0	$ 0
[1]Expires in September 2027.[2]Includes outstanding commercial paper.

Borrowings and Other Financin_6

Borrowings and Other Financing Instruments (Details) - Series Due June 15, 2053 - Bonds [Member] $ in Millions	Jun. 30, 2023 USD ($)
Short-term Debt [Line Items]
Debt Instrument, Face Amount	$ 125
Debt Instrument, Interest Rate, Stated Percentage	5.30%

Revenues (Details)

Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Total revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ 260	$ 278	$ 591	$ 606
Regulated Electric | Total revenues
Disaggregation of Revenue [Line Items]
Total revenues	236	243	490	493
Regulated Natural Gas | Total revenues
Disaggregation of Revenue [Line Items]
Total revenues	24	35	101	113
Retail
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	214	221	493	496
Retail | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	81	85	204	208
Retail | C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	131	134	285	284
Retail | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2	2	4	4
Retail | Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	192	188	396	387
Retail | Regulated Electric | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	68	67	150	148
Retail | Regulated Electric | C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	122	119	242	235
Retail | Regulated Electric | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2	2	4	4
Retail | Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	22	33	97	109
Retail | Regulated Natural Gas | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	13	18	54	60
Retail | Regulated Natural Gas | C&I
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	9	15	43	49
Retail | Regulated Natural Gas | Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	0	0	0
Interchange
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	41	54	89	103
Interchange | Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	41	53	88	101
Interchange | Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0	1	1	2
Total revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	255	275	582	599
Total revenue from contracts with customers | Regulated Electric
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	233	241	484	488
Total revenue from contracts with customers | Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	22	34	98	111
Alternative revenue and other
Disaggregation of Revenue [Line Items]
Alternative revenue and other	5	3	9	7
Alternative revenue and other | Regulated Electric
Disaggregation of Revenue [Line Items]
Alternative revenue and other	3	2	6	5
Alternative revenue and other | Regulated Natural Gas
Disaggregation of Revenue [Line Items]
Alternative revenue and other	$ 2	$ 1	$ 3	$ 2

Income Taxes (Details)

Income Taxes (Details)		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21%	21%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent		6.20%	6.20%
Effective Income Tax Rate Reconciliation, Other Regulatory Items, Percent	[1]	(3.50%)	(4.00%)
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent		(0.90%)	(0.70%)
Effective Income Tax Rate Reconciliation, Percent		22.80%	22.50%
[1]Plant regulatory differences primarily relate to the credit of excess deferred taxes to customers through the average rate assumption method. Income tax benefits associated with the credit are offset by corresponding revenue reductions.

Fair Value of Financial Asset_3

Fair Value of Financial Assets and Liabilities - Commodity Derivatives (Details) $ in Millions	Jun. 30, 2023 USD ($)
Cash Flow Hedges
Derivative [Line Items]
Derivative Instruments in Hedges, at Fair Value, Net	$ 0

Fair Value of Financial Asset_4

Fair Value of Financial Assets and Liabilities - Recurring Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Prepayments and other	$ 5	$ 11

Fair Value of Financial Asset_5

Fair Value of Financial Assets and Liabilities - Fair Value of Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt, Carrying Amount	$ 1,211	$ 1,086
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt, Fair Value	$ 1,107	$ 980

Benefit Plans and Other Postr_3

Benefit Plans and Other Postretirement Benefits (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended		6 Months Ended
		Jan. 31, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Components of Net Periodic Benefit Cost [Abstract]
Operating and maintenance expenses			$ 57	$ 54	$ 115	$ 107
Pension Plan [Member]
Components of Net Periodic Benefit Cost [Abstract]
Service cost			1	1	2	2
Interest cost (a)	[1]		2	1	3	2
Expected return on plan assets (a)	[1]		(2)	(2)	(4)	(4)
Amortization of net loss (a)	[1]		0	1	1	2
Net benefit cost recognized for financial reporting			$ 1	$ 1	$ 2	$ 2
Contributions to pension plans		$ 4
Pension Plan [Member] | Parent Company [Member]
Components of Net Periodic Benefit Cost [Abstract]
Contributions to pension plans		$ 50
[1]The components of net periodic cost other than the service cost component are included in the line item “Other income, net” in the consolidated statements of income or capitalized on the consolidated balance sheets as a regulatory asset.

Commitments and Contingencies G

Commitments and Contingencies Gas Trading Litigation (Details)	Jun. 30, 2023
Gas Trading Litigation
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number	1

MISO ROE Complaints (Details)

MISO ROE Complaints (Details) - Federal Energy Regulatory Commission (FERC) - FERC Proceeding, MISO ROE Complaint - NSP Minnesota and NSP Wisconsin [Member] [Member]	1 Months Ended
	Feb. 28, 2015	Nov. 30, 2013
Rate Matters [Abstract]
Public Utilities, Base Return On Equity Charged To Customers Through Transmission Formula Rates	12.38%	12.38%
Public Utilities, ROE Applicable To Transmission Formula Rates In The MISO Region, Recommended By Third Parties	8.67%	9.15%

Commitments and Contingencies (

Commitments and Contingencies (Details) - Enviromental Requirements $ in Millions	Jun. 30, 2023 USD ($)
Loss Contingencies [Line Items]
Liability for estimated cost to comply with regulation	$ 5
Gain Contingencies [Line Items]
Liability for estimated cost to comply with regulation	$ 5
Plants required for improvements	2
Public Utilities, General Disclosures [Line Items]
Plants required for improvements	2
Other MGP, Landfill, or Disposal Sites [Domain]
Loss Contingencies [Line Items]
Number of identified MGP sites under current investigation and/or remediation	1
Gain Contingencies [Line Items]
Number of identified MGP sites under current investigation and/or remediation	1

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2023		Jun. 30, 2022		Jun. 30, 2023		Jun. 30, 2022
Segment Reporting Information [Line Items]
Net income		$ 26		$ 15		$ 71		$ 62
Regulated and Unregulated Operating Revenue		260		278		591		606
Affiliate Revenue		51		52
Natural gas		24		35		101		113
Total revenues
Segment Reporting Information [Line Items]
Regulated and Unregulated Operating Revenue	[1]					592		606
Intersegment Eliminations
Segment Reporting Information [Line Items]
Net income						(1)		0
Regulated Electric
Segment Reporting Information [Line Items]
Net income		30		15		63		47
Regulated Electric | Total revenues
Segment Reporting Information [Line Items]
Regulated Operating Revenue, Electric		236	[2]	243	[2]	490	[1]	493	[1]
Regulated Natural Gas
Segment Reporting Information [Line Items]
Net income		(3)		(1)		8		14
Revenues Including Intersegment Revenues		24		35		102		113
Regulated Natural Gas | Total revenues
Segment Reporting Information [Line Items]
Natural gas						101		113
Regulated Natural Gas | Intersegment Eliminations
Segment Reporting Information [Line Items]
Natural gas						1		0
All Other
Segment Reporting Information [Line Items]
Net income		$ (1)		$ 1		$ 0		$ 1
[1]Total revenues include $101 million and $99 million of affiliate electric revenue for the six months ended June 30, 2023 and 2022, respectively.[2]Total revenues include $51 million and $52 million of affiliate electric revenue for the three months ended June 30, 2023 and 2022, respectively.