NiSource (NI) 10-K 23 Feb 22 2021 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Feb. 15, 2022	Jun. 30, 2021
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-16189
Entity Registrant Name	NiSource Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	35-2108964
Entity Address, Address Line One	801 East 86th Avenue
Entity Address, City or Town	Merrillville,
Entity Address, State or Province	IN
Entity Address, Postal Zip Code	46410
City Area Code	(877)
Local Phone Number	647-5990
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 9,579,675,045
Entity Common Stock, Shares Outstanding		405,385,010
Entity Central Index Key	0001111711
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	false
Documents Incorporated by Reference [Text Block]	Part III of this report incorporates by reference specific portions of the Registrant’s Notice of Annual Meeting and Proxy Statement relating to the Annual Meeting of Stockholders to be held on May 24, 2022.
Series A Corporate Units
Document Information [Line Items]
Title of 12(b) Security	Series A Corporate Units
Trading Symbol	NIMC
Security Exchange Name	NYSE
Common Stock
Document Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	NI
Security Exchange Name	NYSE
Preferred Stock
Document Information [Line Items]
Title of 12(b) Security	Depositary Shares, each representing a 1/1,000th ownership interest in a share of 6.50% Series B Fixed-Rate Reset Cumulative Redeemable Perpetual
Trading Symbol	NI PR B
Security Exchange Name	NYSE

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2021
Auditor [Line Items]
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Location	Columbus, Ohio
Auditor Firm ID	34

Statements Of Consolidated Inco

Statements Of Consolidated Income (Loss) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Revenues
Customer revenues	$ 4,731.3	$ 4,473.2	$ 5,053.4
Other revenues	168.3	208.5	155.5
Total Operating Revenues	4,899.6	4,681.7	5,208.9
Operating Expenses
Cost of energy	1,392.3	1,109.3	1,534.8
Operation and maintenance	1,456	1,585.9	1,354.7
Depreciation and amortization	748.4	725.9	717.4
Impairment of goodwill and intangible assets	0	0	414.5
Loss on sale of assets, net	7.7	410.6	0
Other taxes	288.3	299.2	296.8
Total Operating Expenses	3,892.7	4,130.9	4,318.2
Operating Income	1,006.9	550.8	890.7
Other Income (Deductions)
Interest expense, net	(341.1)	(370.7)	(378.9)
Other, net	40.8	32.1	(5.2)
Loss on early extinguishment of long-term debt	0	(243.5)	0
Total Other Deductions, Net	(300.3)	(582.1)	(384.1)
Income (Loss) before Income Taxes	706.6	(31.3)	506.6
Income Taxes	117.8	(17.1)	123.5
Net Income (Loss)	588.8	(14.2)	383.1
Net income attributable to noncontrolling interest	3.9	3.4	0
Net Income (Loss) attributable to NiSource	584.9	(17.6)	383.1
Preferred dividends	(55.1)	(55.1)	(55.1)
Net Income (Loss) Available to Common Shareholders	$ 529.8	$ (72.7)	$ 328
Earnings Per Share
Basic Earnings (Loss) Per Share	$ 1.35	$ (0.19)	$ 0.88
Diluted Earnings (Loss) Per Share	$ 1.27	$ (0.19)	$ 0.87
Average common shares outstanding - Basic	393,600	384,300	374,600
Diluted Average Common Shares	417,300	384,300	376,000

Statements of Consolidated Comp

Statements of Consolidated Comprehensive Income (Loss) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Income (Loss)		$ 588.8	$ (14.2)	$ 383.1
Other comprehensive income (loss):
Net unrealized gain (loss) on available-for-sale securities	[1]	(3.9)	2.7	5.7
Net unrealized gain (loss) on cash flow hedges	[2]	25.4	(70.7)	(64.2)
Unrecognized pension and OPEB benefit (costs)	[3]	8.4	3.9	3.1
Total other comprehensive income (loss)		29.9	(64.1)	(55.4)
Total Comprehensive Income (Loss)		$ 618.7	$ (78.3)	$ 327.7
[1]	Net unrealized gain (loss) on available-for-sale securities, net of $1.0 million tax benefit, $0.7 million tax expense and $1.5 million tax expense in 2021, 2020 and 2019, respectively.
[2]	Net unrealized gain (loss) on derivatives qualifying as cash flow hedges, net of $8.4 million tax expense, $23.4 million tax benefit and $21.2 million tax benefit in 2021, 2020 and 2019, respectively.
[3]	Unrecognized pension and OPEB benefit, net of $3.8 million tax expense, $0.1 million tax benefit and $1.6 million tax expense in 2021, 2020 and 2019, respectively.

Statements of Consolidated Co_2

Statements of Consolidated Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax	$ (1)	$ 0.7	$ 1.5
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax, Parent	8.4	(23.4)	(21.2)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	$ (3.8)	$ 0.1	$ (1.6)

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions		Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment
Plant		$ 25,171.3	$ 24,179.9
Accumulated depreciation and amortization		(7,289.5)	(7,560.4)
Net Property, Plant and Equipment	[1]	17,881.8	16,619.5
Investments and Other Assets
Unconsolidated affiliates		0.8	0
Available-for-sale debt securities (amortized cost of $169.3 and $163.9, allowance for credit losses of $0.2 and $0.5, respectively)		171.8	170.9
Other investments		87.1	81.1
Total Investments and Other Assets		259.7	252
Current Assets
Cash and cash equivalents		84.2	116.5
Restricted cash		10.7	9.1
Accounts receivable		849.1	843.6
Allowance for credit losses		(23.5)	(52.3)
Accounts receivable, net		825.6	791.3
Gas inventory		327.4	191.2
Materials and supplies, at average cost		139.1	141.5
Electric production fuel, at average cost		32.2	68.4
Exchange gas receivable		99.6	34.1
Regulatory assets		206.2	135.7
Deferred property taxes		91	85.6
Prepayments and other		104.8	86
Total Current Assets	[1]	1,920.8	1,659.4
Other Assets
Regulatory assets		2,286	1,794.8
Goodwill		1,485.9	1,485.9
Deferred charges and other		322.7	228.9
Total Other Assets		4,094.6	3,509.6
Total Assets		24,156.9	22,040.5
Stockholders' Equity
Common stock - $0.01 par value, 600,000,000 shares authorized; 405,303,023 and 391,760,051 shares outstanding, respectively		4.1	3.9
Preferred stock - $0.01 par value, 20,000,000 shares authorized; 1,302,500 and 440,000 shares outstanding, respectively		1,546.5	880
Treasury stock		(99.9)	(99.9)
Additional paid-in capital		7,204.3	6,890.1
Retained deficit		(1,580.9)	(1,765.2)
Accumulated other comprehensive loss		(126.8)	(156.7)
Total NiSource Stockholders' Equity		6,947.3	5,752.2
Noncontrolling interest in consolidated subsidiaries		325.6	85.6
Total Stockholders’ Equity		7,272.9	5,837.8
Long-term debt, excluding amounts due within one year		9,183.4	9,219.8
Total Capitalization		16,456.3	15,057.6
Current Liabilities
Current portion of long-term debt		58.1	23.3
Short-term borrowings		560	503
Accounts payable		697.8	589
Customer deposits and credits		237.9	243.3
Taxes accrued		277.1	244.1
Interest accrued		105.5	104.7
Exchange gas payable		107.7	48.5
Regulatory liabilities		137.4	161.3
Accrued compensation and employee benefits		182.7	141.8
Other accruals		382	220.4
Total Current Liabilities		2,746.2	2,279.4
Other Liabilities
Deferred Income Tax Liabilities, Net		1,659.4	1,470.6
Accrued liability for postretirement and postemployment benefits		292.5	336.1
Regulatory liabilities		1,842.6	1,904.2
Asset retirement obligations		469.7	477.1
Other noncurrent liabilities		690.2	515.5
Total Other Liabilities(1)		4,954.4	4,703.5
Total Capitalization and Liabilities		$ 24,156.9	$ 22,040.5
[1]	(1) Includes $695.9 million and $175.6 million in 2021 and 2020, respectively, of net property, plant and equipment assets and $14.3 million and $1.7 million in 2021 and 2020, respectively, of current assets of consolidated VIEs that may be used only to settle obligations of the consolidated VIEs. Refer to Note 4, "Variable Interest Entities" for additional information.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions		Dec. 31, 2021	Dec. 31, 2020
Amortized Cost		$ 169.3	$ 163.9
Allowance for Credit Loss		0.2	0.5
Net Property, Plant and Equipment	[1]	17,881.8	16,619.5
Current assets	[1]	$ 1,920.8	$ 1,659.4
Common stock, par value		$ 0.01	$ 0.01
Common stock, shares authorized		600,000,000	600,000,000
Common stock, shares outstanding		405,303,023	391,760,051
Preferred Stock, Par or Stated Value Per Share		$ 0.01	$ 0.01
Preferred Stock, Shares Authorized		20,000,000	20,000,000
Preferred Stock, Shares Outstanding		1,302,500	440,000
Current liabilities		$ 2,746.2	$ 2,279.4
Liabilities, Noncurrent		4,954.4	4,703.5
Rosewater
Current assets		6.2	1.7
Current liabilities		2.5	15.3
Consolidated Variable Interest Entities
Net Property, Plant and Equipment		695.9	175.6
Current assets		14.3	1.7
Current liabilities		10	15.3
Liabilities, Noncurrent		$ 20.5	$ 5.6
[1]	(1) Includes $695.9 million and $175.6 million in 2021 and 2020, respectively, of net property, plant and equipment assets and $14.3 million and $1.7 million in 2021 and 2020, respectively, of current assets of consolidated VIEs that may be used only to settle obligations of the consolidated VIEs. Refer to Note 4, "Variable Interest Entities" for additional information.

Statements Of Consolidated Cash

Statements Of Consolidated Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Activities
Net Income (Loss)	$ 588.8	$ (14.2)	$ 383.1
Adjustments to Reconcile Net Income (Loss) to Net Cash from Operating Activities:
Loss on early extinguishment of debt	0	243.5	0
Depreciation and amortization	748.4	725.9	717.4
Deferred income taxes and investment tax credits	111.9	(29)	118.2
Stock compensation expense and 401(k) profit sharing contribution	24.3	17.4	25.9
Impairment of goodwill and intangible assets	0	0	414.5
Loss (gain) on sale of assets	5.6	409.8	(0.6)
Other adjustments	(0.7)	(0.3)	(0.1)
Changes in Assets and Liabilities:
Accounts receivable	(40.3)	(3.9)	187.8
Inventories	(112.9)	(1.5)	(2)
Accounts payable	54.9	(29.7)	(299.9)
Exchange gas receivable/payable	(114.2)	(6.9)	55.5
Other accruals	43	(175.1)	138.3
Prepayments and other current assets	(36.6)	(5.9)	(33.6)
Regulatory assets/liabilities	76.8	70.8	(85.6)
Postretirement and postemployment benefits	(96.4)	(103.6)	(21.1)
Deferred charges and other noncurrent assets	(4.7)	(15)	(76.1)
Other noncurrent liabilities	(30)	21.7	61.6
Net Cash Flows from Operating Activities	1,217.9	1,104	1,583.3
Investing Activities
Capital expenditures	(1,838)	(1,758.1)	(1,802.4)
Cost of removal	(121.1)	(138.2)	(113.2)
Proceeds from disposition of assets	0.7	1,115.9	0.4
Purchases of available-for-sale securities	(102.9)	(144.7)	(140.4)
Sales of available-for-sale securities	97.8	131.4	132.1
Payment to renewable generation asset developer	(240.4)	(85.3)	0
Other investing activities	(1)	(0.1)	1.1
Net Cash Flows used for Investing Activities	(2,204.9)	(879.1)	(1,922.4)
Financing Activities
Proceeds from issuance of long-term debt	0	2,974	750
Repayments of long-term debt and finance lease obligations	(25.7)	(1,622)	(51.6)
Issuance of short-term debt (maturity > 90 days)	0	1,350	600
Repayment of short-term debt (maturity > 90 days)	0	(2,200)	(700)
Change in short-term borrowings, net (maturity ≤ 90 days)	57	(420.1)	(104)
Issuance of common stock, net of issuance costs	299.6	211.4	244.4
Equity costs, premiums and other debt related costs	(18.2)	(246.5)	(17.8)
Contributions from noncontrolling interest	245.1	82.2	0
Distributions to noncontrolling interest	(0.6)	0	0
Issuance of equity units, net of underwriting costs	839.9	0	0
Dividends paid - common stock	(345.2)	(321.6)	(298.5)
Dividends paid - preferred stock	(55.1)	(55.1)	(56.1)
Contract liability payment	(40.5)	0	0
Net Cash Flows from Financing Activities	956.3	(247.7)	366.4
Change in cash, cash equivalents and restricted cash	(30.7)	(22.8)	27.3
Cash, cash equivalents and restricted cash at beginning of period	125.6	148.4	121.1
Cash, Cash Equivalents and Restricted Cash at End of Period	$ 94.9	$ 125.6	$ 148.4

Statements Of Consolidated Ca_2

Statements Of Consolidated Cash Flows (Schedule of Balance Sheet Reconciliation) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash and Cash Equivalents, at Carrying Value	$ 84.2	$ 116.5	$ 139.3
Restricted cash	10.7	9.1	9.1
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 94.9	$ 125.6	$ 148.4	$ 121.1

Statements Of Consolidated Stoc

Statements Of Consolidated Stockholders' Equity - USD ($) $ in Millions	Total	Common Stock	Preferred Stock	[1]	Treasury Stock	Additional Paid-in Capital	Retained Deficit	Accumulated Other Comprehensive Loss	Noncontrolling Interest in Consolidated Subsidiaries
Beginning Balance at Dec. 31, 2018	$ 5,750.9	$ 3.8	$ 880		$ (99.9)	$ 6,403.5	$ (1,399.3)	$ (37.2)	$ 0
Comprehensive Income (Loss):
Net Income (Loss)	383.1	0	0		0	0	383.1	0	0
Other Comprehensive Income (Loss), Net of Tax	(55.4)	0	0		0	0	0	(55.4)	0
Dividends:
Common stock	(298.5)	0	0		0	0	(298.5)	0	0
Preferred stock	(56.1)	0	0		0	0	(56.1)	0	0
Stock issuances:
Employee stock purchase plan	5.6	0	0		0	5.6	0	0	0
Long-term incentive plan	10.4	0	0		0	10.4	0	0	0
401(k) and profit sharing	17.6	0	0		0	17.6	0	0	0
ATM Program	229.1	0	0		0	229.1	0	0	0
Ending Balance at Dec. 31, 2019	5,986.7	3.8	880		(99.9)	6,666.2	(1,370.8)	(92.6)	0
Comprehensive Income (Loss):
Net Income (Loss)	(14.2)	0	0		0	0	(17.6)	0	3.4
Other Comprehensive Income (Loss), Net of Tax	(64.1)	0	0		0	0	0	(64.1)	0
Dividends:
Common stock	(321.7)	0	0		0	0	(321.7)	0	0
Preferred stock	(55.1)	0	0		0	0	(55.1)	0	0
Contribution from noncontrolling interest	82.2	0	0		0	0	0	0	82.2
Stock issuances:
Employee stock purchase plan	5.7	0	0		0	5.7	0	0	0
Long-term incentive plan	8.4	0	0		0	8.4	0	0	0
401(k) and profit sharing	13.4	0	0		0	13.4	0	0	0
ATM Program	196.5	0.1	0		0	196.4	0	0	0
Ending Balance at Dec. 31, 2020	5,837.8	3.9	880		(99.9)	6,890.1	(1,765.2)	(156.7)	85.6
Comprehensive Income (Loss):
Net Income (Loss)	588.8	0	0		0	0	584.9	0	3.9
Other Comprehensive Income (Loss), Net of Tax	29.9	0	0		0	0	0	29.9	0
Dividends:
Common stock	(345.5)	0	0		0	0	(345.5)	0	0
Preferred stock	(55.1)	0	0		0	0	(55.1)	0	0
Contribution from noncontrolling interest	236.7	0	0		0	0	0	0	236.7
Distributions to Noncontrolling Interest Holders	(0.6)	0	0		0	0	0	0	(0.6)
Stock issuances:
Equity Units	666.5	0	666.5		0	0	0	0	0
Employee stock purchase plan	5	0	0		0	5	0	0	0
Long-term incentive plan	11.8	0	0		0	11.8	0	0	0
401(k) and profit sharing	9.5	0	0		0	9.5	0	0	0
ATM Program	288.1	0.2	0		0	287.9	0	0	0
Ending Balance at Dec. 31, 2021	$ 7,272.9	$ 4.1	$ 1,546.5		$ (99.9)	$ 7,204.3	$ (1,580.9)	$ (126.8)	$ 325.6
[1]	Series A, Series B, and Series C shares have an aggregate liquidation preference of $400M, $500M, and $863M, respectively. See Note 13, "Equity," for additional information.

Statements Of Consolidated St_2

Statements Of Consolidated Stockholders' Equity (Shares) - shares shares in Thousands		Total	Common Stock	Treasury Stock	Preferred Stock
Beginning Balance at Dec. 31, 2018		372,363	376,326	3,963	420
Issued:
Preferred stock	[1]	0	0	0	20
Employee stock purchase plan		201	201	0	0
Long-term incentive plan		518	518	0	0
401(k) and profit sharing plan		631	631	0	0
ATM Program		8,423	8,423	0	0
Ending Balance at Dec. 31, 2019		382,136	386,099	3,963	440
Issued:
Equity Units		0	0	0	(863)	[1]
Employee stock purchase plan		236	236	0	0
Long-term incentive plan		385	385	0	0
401(k) and profit sharing plan		544	544	0	0
ATM Program		8,459	8,459	0	0
Ending Balance at Dec. 31, 2020		391,760	395,723	3,963	440
Issued:
Employee stock purchase plan		209	209	0	0
Long-term incentive plan		418	418	0	0
401(k) and profit sharing plan		391	391	0	0
ATM Program		12,525	12,525	0	0
Ending Balance at Dec. 31, 2021		405,303	409,266	3,963	1,303
[1]	See Note 13, "Equity," for additional information.

Statements of Consolidated St_3

Statements of Consolidated Stockholders' Equity (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Common Stock, Dividends, Per Share, Declared	$ 0.88	$ 0.84	$ 0.80
Series A Preferred Stock
Preferred Stock, Liquidation Preference, Value	$ 400	$ 400	$ 400
Series B Preferred Stock
Preferred Stock, Liquidation Preference, Value	500	$ 500	$ 500
Series C Preferred Stock
Preferred Stock, Liquidation Preference, Value	$ 863

Nature of Operations And Summar

Nature of Operations And Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations and Summary of Significant Accounting Policies	Nature of Operations and Summary of Significant Accounting Policies A. Company Structure and Principles of Consolidation. We are an energy holding company incorporated in Delaware and headquartered in Merrillville, Indiana. Our subsidiaries are fully regulated natural gas and electric utility companies serving approximately 3.7 million customers in six states. We generate substantially all of our operating income through these rate-regulated businesses. The consolidated financial statements include the accounts of us, our majority-owned subsidiaries, and VIEs of which we are the primary beneficiary after the elimination of all intercompany accounts and transactions. B. Use of Estimates. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. C. Cash, Cash Equivalents and Restricted Cash. We consider all highly liquid investments with original maturities of three months or less to be cash equivalents. We report amounts deposited in brokerage accounts for margin requirements as restricted cash. In addition, we have amounts deposited in trusts to satisfy requirements for the provision of various property, liability, workers compensation, and long-term disability insurance, which is classified as restricted cash on the Consolidated Balance Sheets and disclosed with cash and cash equivalents on the Statements of Consolidated Cash Flows. D. Accounts Receivable and Unbilled Revenue. Accounts receivable on the Consolidated Balance Sheets includes both billed and unbilled amounts. Unbilled amounts of accounts receivable relate to a portion of a customer’s consumption of gas or electricity from the last cycle billing date through the last day of the month (balance sheet date). Factors taken into consideration when estimating unbilled revenue include historical usage, customer rates, weather and reasonable and supportable forecasts. Accounts receivable fluctuates from year to year depending in large part on weather impacts and price volatility. Our accounts receivable on the Consolidated Balance Sheets include unbilled revenue, less reserves. The reserve for uncollectible receivables is our best estimate of the amount of probable credit losses in the existing accounts receivable. We determined the reserve based on historical experience and in consideration of current market conditions. Account balances are charged against the allowance when it is anticipated the receivable will not be recovered. Refer to Note 3, "Revenue Recognition," for additional information on customer-related accounts receivable, including amounts related to unbilled revenues. E. Investments in Debt Securities. Our investments in debt securities are carried at fair value and are designated as available-for-sale. These investments are included within “Available-for-sale debt securities” on the Consolidated Balance Sheets. Unrealized gains and losses, net of deferred income taxes, are recorded to accumulated other comprehensive income or loss. At each reporting period these investments are qualitatively and quantitatively assessed to determine whether a decline in fair value below the amortized cost basis has resulted from a credit loss or other factors. Impairments related to credit loss are recorded through an allowance for credit losses. Impairments that are not related to credit losses are included in other comprehensive income and are reflected in the Statements of Consolidated Income (Loss). No material impairment charges were recorded for the years ended December 31, 2021, 2020 or 2019. Refer to Note 18, "Fair Value," for additional information. F. Basis of Accounting for Rate-Regulated Subsidiaries. Rate-regulated subsidiaries account for and report assets and liabilities consistent with the economic effect of the way in which regulators establish rates, if the rates established are designed to recover the costs of providing the regulated service and it is probable that such rates can be charged and collected. Certain expenses and credits subject to utility regulation or rate determination normally reflected in income are deferred on the Consolidated Balance Sheets and are later recognized in income as the related amounts are included in customer rates and recovered from or refunded to customers. We continually evaluate whether or not our operations are within the scope of ASC 980 and rate regulations. As part of that analysis, we evaluate probability of recovery for our regulatory assets. In management’s opinion, our regulated subsidiaries will be subject to regulatory accounting for the foreseeable future. Refer to Note 9, "Regulatory Matters," for additional information. G. Plant and Other Property and Related Depreciation and Maintenance. Property, plant and equipment (principally utility plant) is stated at cost. Our rate-regulated subsidiaries record depreciation using composite rates on a straight-line basis over the remaining service lives of the electric, gas and common properties, as approved by the appropriate regulators. Non-utility property includes renewable generation assets owned by joint ventures of which we are the primary beneficiary and is generally depreciated on a straight-line basis over the life of the associated assets. Refer to Note 6, "Property, Plant and Equipment," for additional information related to depreciation expense. For rate-regulated companies, AFUDC is capitalized on all classes of property except organization costs, land, autos, office equipment, tools and other general property purchases. The allowance is applied to construction costs for that period of time between the date of the expenditure and the date on which such project is placed in service. Our pre-tax rate for AFUDC was 3.3% in 2021, 2.6% in 2020 and 3.0% in 2019. Generally, our subsidiaries follow the practice of charging maintenance and repairs, including the cost of removal of minor items of property, to expense as incurred. When our subsidiaries retire regulated property, plant and equipment, original cost plus the cost of retirement, less salvage value, is charged to accumulated depreciation. However, when it becomes probable a regulated asset will be retired substantially in advance of its original expected useful life or is abandoned, the cost of the asset and the corresponding accumulated depreciation is recognized as a separate asset. If the asset is still in operation, the gross amounts are classified as "Non-Utility and Other " as described in Note 6, "Property, Plant and Equipment." If the asset is no longer operating but still subject to recovery, the net amount is classified in "Regulatory assets" on the Consolidated Balance Sheets. If we are able to recover a full return of and on investment, the carrying value of the asset is based on historical cost. If we are not able to recover a full return on investment, a loss on impairment is recognized to the extent the net book value of the asset exceeds the present value of future revenues discounted at the incremental borrowing rate. When our subsidiaries sell entire regulated operating units, or retire or sell nonregulated properties, the original cost and accumulated depreciation and amortization balances are removed from "Net Property, Plant and Equipment" on the Consolidated Balance Sheets. Any gain or loss is recorded in earnings, unless otherwise required by the applicable regulatory body. Refer to Note 6, "Property, Plant and Equipment," for further information. External and internal costs associated with on-premise computer software developed for internal use are capitalized. Capitalization of such costs commences upon the completion of the preliminary stage of each project. Once the installed software is ready for its intended use, such capitalized costs are amortized on a straight-line basis generally over a period of five years. External and internal up-front implementation costs associated with cloud computing arrangements that are service contracts are deferred on the Consolidated Balance Sheets. Once the installed software is ready for its intended use, such deferred costs are amortized on a straight-line basis to "Operation and maintenance," over the minimum term of the contract plus contractually-provided renewal periods that are reasonable expected to be exercised. H. Goodwill and Other Intangible Assets. Substantially all of our goodwill relates to the excess of cost over the fair value of the net assets acquired in the Columbia acquisition on November 1, 2000. We test our goodwill for impairment annually as of May 1, or more frequently if events and circumstances indicate that goodwill might be impaired. Fair value of our reporting units is determined using a combination of income and market approaches. See Note 7, "Goodwill and Other Intangible Assets," for additional information. I. Accounts Receivable Transfer Program. Certain of our subsidiaries have agreements with third parties to transfer certain accounts receivable without recourse. These transfers of accounts receivable are accounted for as secured borrowings. The entire gross receivables balance remains on the December 31, 2021 and 2020 Consolidated Balance Sheets. When amounts are securitized, the short-term debt is recorded in the amount of proceeds received from the transferees involved in the transactions. Refer to Note 16, "Short Term Borrowings," for further information. J. Gas Cost and Fuel Adjustment Clause. Our regulated subsidiaries defer most differences between gas and fuel purchase costs and the recovery of such costs in revenues and adjust future billings for such deferrals on a basis consistent with applicable state-approved tariff provisions. These deferred balances are recorded as "Regulatory assets" or "Regulatory liabilities," as appropriate, on the Consolidated Balance Sheets. Refer to Note 9, "Regulatory Matters," for additional information. K. Inventory. Both the LIFO inventory methodology and the weighted average cost methodology are used to value natural gas in storage, as approved by regulators for all of our regulated subsidiaries. Inventory valued using LIFO was $44.9 million and $42.3 million at December 31, 2021 and 2020, respectively. Based on the average cost of gas using the LIFO method, the estimated replacement cost of gas in storage was less than the stated LIFO cost by $13.6 million and $19.6 million at December 31, 2021 and 2020, respectively. As all LIFO inventory costs are collected from customers through our rate- regulated subsidiaries, no inventory impairment has been recorded. Gas inventory valued using the weighted average cost methodology was $282.4 million at December 31, 2021 and $148.8 million at December 31, 2020. Electric production fuel is valued using the weighted average cost inventory methodology, as approved by NIPSCO's regulator. Materials and supplies are valued using the weighted average cost inventory methodology. L. Accounting for Exchange and Balancing Arrangements of Natural Gas. Our Gas Distribution Operations segment enters into balancing and exchange arrangements of natural gas as part of its operations and off-system sales programs. We record a receivable or payable for any of our respective cumulative gas imbalances, as well as for any gas inventory borrowed or lent under a Gas Distribution Operations exchange agreement. Exchange gas is valued based on individual regulatory jurisdiction requirements (for example, historical spot rate, spot at the beginning of the month). These receivables and payables are recorded as “Exchange gas receivable” or “Exchange gas payable” on our Consolidated Balance Sheets, as appropriate. M. Accounting for Risk Management Activities. We account for our derivatives and hedging activities in accordance with ASC 815. We recognize all derivatives as either assets or liabilities on the Consolidated Balance Sheets at fair value, unless such contracts are exempted as a normal purchase normal sale under the provisions of the standard. The accounting for changes in the fair value of a derivative depends on the intended use of the derivative and resulting designation. We do not offset the fair value amounts recognized for any of our derivative instruments against the fair value amounts recognized for the right to reclaim cash collateral or obligation to return cash collateral for derivative instruments executed with the same counterparty under a master netting arrangement. See Note 10, "Risk Management Activities," for additional information. N. Income Taxes and Investment Tax Credits. We record income taxes to recognize full interperiod tax allocations. Under the asset and liability method, deferred income taxes are provided for the tax consequences of temporary differences by applying enacted statutory tax rates applicable to future years to differences between the financial statement carrying amount and the tax basis of existing assets and liabilities. Investment tax credits associated with regulated operations are deferred and amortized as a reduction to income tax expense over the estimated useful lives of the related properties. To the extent certain deferred income taxes of the regulated companies are recoverable or payable through future rates, regulatory assets and liabilities have been established. Regulatory assets for income taxes are primarily attributable to property-related tax timing differences for which deferred taxes had not been provided in the past, when regulators did not recognize such taxes as costs in the rate-making process. Regulatory liabilities for income taxes are primarily attributable to the regulated companies’ obligation to refund to ratepayers deferred income taxes provided at rates higher than the current Federal income tax rate. Such property-related amounts are credited to ratepayers using either the average rate assumption method or the reverse South Georgia method. Non property-related amounts are credited to ratepayers consistent with state utility commission direction. Pursuant to the Internal Revenue Code and relevant state taxing authorities, we and our subsidiaries file consolidated income tax returns for federal and certain state jurisdictions. We and our subsidiaries are parties to a tax sharing agreement. Income taxes recorded by each party represent amounts that would be owed had the party been separately subject to tax. O. Pension Remeasurement. We utilize a third-party actuary for the purpose of performing actuarial valuations of our defined benefit plans. Annually, as of December 31, we perform a remeasurement for our pension plans. Quarterly, we monitor for significant events, and if a significant event is identified, we perform a qualitative and quantitative assessment to determine if the resulting remeasurement would materially impact the NiSource financial statements. If material, an interim remeasurement is performed. We had one such interim remeasurement in the first quarter of 2021. See Note 12, "Pension and Other Postretirement Benefits," for additional information. P. Environmental Expenditures. We accrue for costs associated with environmental remediation obligations, including expenditures related to asset retirement obligations and cost of removal, when the incurrence of such costs is probable and the amounts can be reasonably estimated, regardless of when the expenditures are actually made. The undiscounted estimated future expenditures are based on currently enacted laws and regulations, existing technology and estimated site-specific costs where assumptions may be made about the nature and extent of site contamination, the extent of cleanup efforts, costs of alternative cleanup methods and other variables. The liability is adjusted as further information is discovered or circumstances change. The accruals for estimated environmental expenditures are recorded on the Consolidated Balance Sheets in “Other accruals” for short-term portions of these liabilities and “Other noncurrent liabilities” for the respective long-term portions of these liabilities. Rate-regulated subsidiaries applying regulatory accounting establish regulatory assets on the Consolidated Balance Sheets to the extent that future recovery of environmental remediation costs is probable through the regulatory process. Refer to Note 8, "Asset Retirement Obligations," and Note 19, "Other Commitments and Contingencies," for further information. Q. Excise Taxes. As an agent for some state and local governments, we invoice and collect certain excise taxes levied by state and local governments on customers and record these amounts as liabilities payable to the applicable taxing jurisdiction. Such balances are presented within "Other accruals" on the Consolidated Balance Sheets. These types of taxes collected from customers, comprised largely of sales taxes, are presented on a net basis affecting neither revenues nor cost of sales. We account for excise taxes for which we are liable by recording a liability for the expected tax with a corresponding charge to “Other taxes” expense on the Statements of Consolidated Income (Loss). R. Accrued Insurance Liabilities. We accrue for insurance costs related to workers compensation, automobile, property, general and employment practices liabilities based on the most probable value of each claim. In general, claim values are determined by professional, licensed loss adjusters who consider the facts of the claim, anticipated indemnification and legal expenses, and respective state rules. Claims are reviewed by us at least quarterly and an adjustment is made to the accrual based on the most current information. S. VIEs and Allocation of Earnings. We fund a significant portion of our renewable generation assets through joint ventures with tax equity partners. We consolidate these joint ventures in accordance with ASC 810 as they are VIEs in which we hold a variable interest, and we control decisions that are significant to the joint ventures' ongoing operations and economic results (i.e., we are the primary beneficiary). These joint ventures are subject to profit sharing arrangements in which the allocation of the joint ventures' cash distributions and tax benefits to members is based on factors other than members' relative ownership percentages. As such, we utilize the HLBV method to allocate proceeds to each partner at the balance sheet date based on the liquidation provisions of the related joint venture's operating agreement and adjusts the amount of the VIE's net income attributable to us and the noncontrolling tax equity member during the period. In each reporting period, the application of HLBV to our consolidated VIEs results in a difference between the amount of profit from the consolidated joint ventures and the amount included in regulated rates. As discussed above in "F. Basis of Accounting for Rate-Regulated Subsidiaries," we are subject to the accounting and reporting requirements of ASC 980. In accordance with these principles, we recognize a regulatory liability or asset for amounts representing the timing difference between the profit earned from the joint ventures and the amount included in regulated rates to recover our approved investments in consolidated joint ventures. The amounts recorded in income will ultimately reflect the amount allowed in regulated rates to recover our investments over the useful life of the projects. The offset to the regulatory liability or asset associated with our renewable investments included in regulated rates is recorded in "Depreciation expense" on the Statements of Consolidated Income (Loss).

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2021
Accounting Standards Update and Change in Accounting Principle [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently Issued Accounting Pronouncements We are currently evaluating the impact of certain ASUs on our Consolidated Financial Statements and Notes to Consolidated Financial Statements, which are described below: In March 2020, the FASB issued ASU 2020-04 Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting and in January 2021, the FASB issued ASU 2021-01 Reference Rate Reform (Topic 848): Scope. These pronouncements provide temporary optional expedients and exceptions for applying GAAP principles to contract modifications and hedging relationships to ease the financial reporting burdens of the expected market transition from LIBOR and other interbank offered rates to alternative reference rates. These pronouncements are effective upon issuance on March 12, 2020, and will apply through December 31, 2022. We have evaluated the temporary expedients and options available under this guidance and identified the financial instruments to which the expedients could be applied, if deemed necessary. As of December 31, 2021, we have not applied any expedients and options available under these ASUs. In November 2021, the FASB issued ASU 2021-10 Government Assistance (Topic 832): Disclosures by Business Entities about Government Assistance . This pronouncement requires business entities to provide certain disclosures when they have received government assistance and use a grant or contribution accounting model by analogy to other accounting guidance. This pronouncement is applicable for financial statements issued for annual periods beginning after December 15, 2021. We are currently evaluating the impact of adoption, if any, on the Notes to Consolidated Financial Statements. Recently Adopted Accounting Pronouncements In August 2020, the FASB issued ASU 2020-06 Debt with Conversion and Other Options (Subtopic 470-20) and Derivative and Hedging - Contracts in Entity's Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity's Own Equity. This pronouncement simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity's own equity. Specifically, the ASU "simplifies accounting for convertible instruments by removing major separation models required under current GAAP." In addition, the ASU "removes certain settlement conditions that are required for equity contracts to qualify for it" and "simplifies the diluted earnings per share (EPS) calculations in certain areas." Finally, this ASU "eliminates the cash conversion and beneficial conversion feature models that require an issuer of certain convertible debt and preferred stock to separately account for embedded conversion features as a component of equity." This pronouncement is effective for the annual period beginning after December 15, 2021, and interim periods within those fiscal years. This accounting pronouncement will impact the denominator in the calculation of diluted EPS for our Equity Units. Beginning Q1 2022, we will be required to assume share settlement of the remaining purchase contract payment balance when applying the if-converted method. Moreover, we will also be required to utilize the average share price for the period instead of the end of period price. We have adopted this ASU on its effective date.

Revenue Recognition

Revenue Recognition	12 Months Ended
	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer	Revenue Recognition Customer Revenues. Substantially all of our revenues are tariff-based. Under ASC 606, the recipients of our utility service meet the definition of a customer, while the operating company tariffs represent an agreement that meets the definition of a contract, which creates enforceable rights and obligations. Customers in certain of our jurisdictions participate in programs that allow for a fixed payment each month regardless of usage. Payments received that exceed the value of gas or electricity actually delivered are recorded as a liability and presented in "Customer Deposits and Credits" on the Consolidated Balance Sheets. Amounts in this account are reduced and revenue is recorded when customer usage exceeds payments received. We have identified our performance obligations created under tariff-based sales as 1) the commodity (natural gas or electricity, which includes generation and capacity) and 2) delivery. These commodities are sold and / or delivered to and generally consumed by customers simultaneously, leading to satisfaction of our performance obligations over time as gas or electricity is delivered to customers. Due to the at-will nature of utility customers, performance obligations are limited to the services requested and received to date. Once complete, we generally maintain no additional performance obligations. Transaction prices for each performance obligation are generally prescribed by each operating company’s respective tariff. Rates include provisions to adjust billings for fluctuations in fuel and purchased power costs and cost of natural gas. Revenues are adjusted for differences between actual costs, subject to reconciliation, and the amounts billed in current rates. Under or over recovered revenues related to these cost recovery mechanisms are included in "Regulatory Assets" or "Regulatory Liabilities" on the Consolidated Balance Sheets and are recovered from or returned to customers through adjustments to tariff rates. As we provide and deliver service to customers, revenue is recognized based on the transaction price allocated to each performance obligation. Distribution revenues are generally considered daily or "at-will" contracts as customers may cancel their service at any time (subject to notification requirements), and revenue generally represents the amount we are entitled to bill customers. In addition to tariff-based sales, our Gas Distribution Operations segment enters into balancing and exchange arrangements of natural gas as part of our operations and off-system sales programs. Performance obligations for these types of sales include transportation and storage of natural gas and can be satisfied at a point in time or over a period of time, depending on the specific transaction. For those transactions that span a period of time, we record a receivable or payable for any cumulative gas imbalances, as well as for any gas inventory borrowed or lent under a Gas Distributions Operations exchange agreement. Revenue Disaggregation and Reconciliation. We disaggregate revenue from contracts with customers based upon reportable segment as well as by customer class. The Gas Distribution Operations segment provides natural gas service and transportation for residential, commercial and industrial customers in Ohio, Pennsylvania, Virginia, Kentucky, Maryland and Indiana. The Electric Operations segment provides electric service in 20 counties in the northern part of Indiana. The tables below reconcile revenue disaggregation by customer class to segment revenue as well as to revenues reflected on the Statements of Consolidated Income (Loss): Year Ended December 31, 2021 (in millions) Gas Distribution Operations Electric Operations Corporate and Other (2) Total Customer Revenues (1) Residential $ 2,109.4 $ 567.9 $ — $ 2,677.3 Commercial 722.4 534.9 — 1,257.3 Industrial 195.7 493.4 — 689.1 Off-system 71.3 — — 71.3 Miscellaneous 27.3 8.2 0.8 36.3 Total Customer Revenues $ 3,126.1 $ 1,604.4 $ 0.8 $ 4,731.3 Other Revenues 45.1 91.9 31.3 168.3 Total Operating Revenues $ 3,171.2 $ 1,696.3 $ 32.1 $ 4,899.6 (1) Customer revenue amounts exclude intersegment revenues. See Note 23, "Segments of Business," for discussion of intersegment revenues. (2) Other revenues related to the Transition Services Agreement entered into in connection with the sale of the Massachusetts Business. Year Ended December 31, 2020 (in millions) Gas Distribution Operations Electric Operations Corporate and Other (2) Total Customer Revenues (1) Residential $ 2,075.0 $ 527.8 $ — $ 2,602.8 Commercial 670.5 480.3 — 1,150.8 Industrial 212.8 412.1 — 624.9 Off-system 41.0 — — 41.0 Miscellaneous 32.7 20.2 0.8 53.7 Total Customer Revenues $ 3,032.0 $ 1,440.4 $ 0.8 $ 4,473.2 Other Revenues 96.1 95.5 16.9 208.5 Total Operating Revenues $ 3,128.1 $ 1,535.9 $ 17.7 $ 4,681.7 (1) Customer revenue amounts exclude intersegment revenues. See Note 23, "Segments of Business," for discussion of intersegment revenues. (2) Other revenues related to the Transition Services Agreement entered into in connection with the sale of the Massachusetts Business. Year Ended December 31, 2019 (in millions) Gas Distribution Operations Electric Operations Corporate and Other Total Customer Revenues (1) Residential $ 2,309.0 $ 481.6 $ — $ 2,790.6 Commercial 771.3 486.6 — 1,257.9 Industrial 245.2 607.7 — 852.9 Off-system 77.7 — — 77.7 Miscellaneous 52.0 21.5 0.8 74.3 Total Customer Revenues $ 3,455.2 $ 1,597.4 $ 0.8 $ 5,053.4 Other Revenues 54.5 101.0 — 155.5 Total Operating Revenues $ 3,509.7 $ 1,698.4 $ 0.8 $ 5,208.9 (1) Customer revenue amounts exclude intersegment revenues. See Note 23, "Segments of Business," for discussion of intersegment revenues. Other Revenues. As permitted by accounting principles generally accepted in the United States, regulated utilities have the ability to earn certain types of revenue that are outside the scope of ASC 606. These revenues primarily represent revenue earned under alternative revenue programs. Alternative revenue programs represent regulator-approved mechanisms that allow for the adjustment of billings and revenue for certain approved programs. We maintain a variety of these programs, including demand side management initiatives that recover costs associated with the implementation of energy efficiency programs, as well as normalization programs that adjust revenues for the effects of weather or other external factors. Additionally, we maintain certain programs with future test periods that operate similarly to FERC formula rate programs and allow for recovery of costs incurred to replace aging infrastructure. When the criteria to recognize alternative revenue have been met, we establish a regulatory asset and present revenue from alternative revenue programs on the Statements of Consolidated Income (Loss) as “Other revenues.” When amounts previously recognized under alternative revenue accounting guidance are billed, we reduce the regulatory asset and record a customer account receivable. Customer Accounts Receivable. Accounts receivable on our Consolidated Balance Sheets includes both billed and unbilled amounts, as well as certain amounts that are not related to customer revenues. Unbilled amounts of accounts receivable relate to a portion of a customer’s consumption of gas or electricity from the date of the last cycle billing through the last day of the month (balance sheet date). Factors taken into consideration when estimating unbilled revenue include historical usage, customer rates and weather. A significant portion of our operations are subject to seasonal fluctuations in sales. During the heating season, primarily from November through March, revenues and receivables from gas sales are more significant than in other months. The opening and closing balances of customer receivables for the year ended December 31, 2021, are presented in the table below. We had no significant contract assets or liabilities during the period. Additionally, we have not incurred any significant costs to obtain or fulfill contracts. (in millions) Customer Accounts Receivable, Billed (less reserve) Customer Accounts Receivable, Unbilled (less reserve) Balance as of December 31, 2020 $ 400.0 $ 327.2 Balance as of December 31, 2021 459.6 337.0 Utility revenues are billed to customers monthly on a cycle basis. We expect that substantially all customer accounts receivable will be collected following customer billing, as this revenue consists primarily of periodic, tariff-based billings for service and usage. We maintain common utility credit risk mitigation practices, including requiring deposits and actively pursuing collection of past due amounts. Our regulated operations also utilize certain regulatory mechanisms that facilitate recovery of bad debt costs within tariff-based rates, which provides further evidence of collectibility. It is probable that substantially all of the consideration to which we are entitled from customers will be collected upon satisfaction of performance obligations. Allowance for Credit Losses. To evaluate for expected credit losses, customer account receivables are pooled based on similar risk characteristics, such as customer type, geography, payment terms, and related macro-economic risks. Expected credit losses are established using a model that considers historical collections experience, current information, and reasonable and supportable forecasts. Internal and external inputs are used in our credit model including, but not limited to, energy consumption trends, revenue projections, actual charge-offs data, recoveries data, shut-offs, customer delinquencies, and final bill data. We continuously evaluate available information relevant to assessing collectability of current and future receivables. We evaluate creditworthiness of specific customers periodically or following changes in facts and circumstances. When we become aware of a specific commercial or industrial customer's inability to pay, an allowance for expected credit losses is recorded for the relevant amount. We also monitor other circumstances that could affect our overall expected credit losses; including, but not limited to, creditworthiness of overall population in service territories, adverse conditions impacting an industry sector, and current economic conditions. At each reporting period, we record expected credit losses to an allowance for credit losses account. When deemed to be uncollectible, customer accounts are written-off. A rollforward of our allowance for credit losses as of December 31, 2021 and December 31, 2020, are presented in the tables below: (in millions) Gas Distribution Operations Electric Operations Corporate and Other Total Balance as of January 1, 2021 $ 41.8 $ 9.7 $ 0.8 $ 52.3 Current period provisions 5.8 1.4 — 7.2 Write-offs charged against allowance (46.7) (7.7) — (54.4) Recoveries of amounts previously written off 18.0 0.4 — 18.4 Balance as of December 31, 2021 $ 18.9 $ 3.8 $ 0.8 $ 23.5 (in millions) Gas Distribution Operations Electric Operations Corporate and Other Total Balance as of January 1, 2020 $ 9.1 $ 3.1 $ 0.8 $ 13.0 Current period provisions 45.3 9.3 — 54.6 Write-offs charged against allowance (26.7) (3.0) — (29.7) Recoveries of amounts previously written off 14.1 0.3 — 14.4 Balance as of December 31, 2020 $ 41.8 $ 9.7 $ 0.8 $ 52.3 In connection with the COVID-19 pandemic, certain state regulatory commissions instituted regulatory moratoriums that impacted our ability to pursue our standard credit risk mitigation practices. Following the issuance of these moratoriums, certain of our regulated operations have been authorized to recognize a regulatory asset for bad debt costs above levels currently recovered in rates. At the balance sheet date, in addition to our evaluation of the allowance for credit losses discussed above, we considered benefits available under governmental COVID-19 relief programs, the impact of unemployment benefits initiatives, and flexible payment plans being offered to customers affected by or experiencing hardship as a result of the pandemic, which could help to mitigate the potential for increasing customer account delinquencies. We also considered the on-time bill payment promotion and robust customer marketing strategy for energy assistance programs that we have implemented. Based upon this evaluation, we have concluded that the allowance for credit losses as of December 31, 2021 adequately reflected the collection risk and net realizable value of our receivables. We have now resumed our common credit mitigation practices in all jurisdictions as these moratoriums have expired (see Note 9, "Regulatory Matters," for additional information on regulatory moratoriums and regulatory assets).

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2021
Variable Interest Entities [Abstract]
Variable Interest Entities	Variable Interest Entities A VIE is an entity in which the controlling interest is determined through means other than a majority voting interest. Refer to Note 1-S, "VIEs and Allocation of Earnings," for information on our accounting policy for the VIEs. We control decisions that are significant to Rosewater and Indiana Crossroads Wind's ongoing operations and economic results. Therefore, we have concluded that we are the primary beneficiary and have consolidated both. Members of the respective joint ventures are NIPSCO (who is the managing member) and tax equity partners. Earnings, tax attributes and cash flows are allocated to both NIPSCO and the tax equity partner in varying percentages by category and over the life of the partnership. Once the tax equity partner has earned their negotiated rate of return and we have reached the agreed upon contractual date, NIPSCO has the option to purchase at fair market value from the tax equity partner the remaining interest in the respective joint venture. NIPSCO has an obligation to purchase, through a PPA at established market rates, 100% of the electricity generated by the joint ventures. Rosewater Rosewater owns and operates 102 MW of nameplate capacity wind generation assets. NIPSCO and the tax equity partner made cash contributions in December 2020 and March 2021 per the equity capital contribution agreement. NIPSCO also assumed an obligation to the developer of the wind generation assets representing the remaining economic interest, which comes due in 2023. From the contributed funds, Rosewater paid $7.4 million and $85.3 million to the developer of the wind generation assets as of December 31, 2021 and 2020, respectively. The developer of the facility is not a partner in the joint venture for federal income tax purposes and does not receive any share of earnings, tax attributes, or cash flows of Rosewater. Indiana Crossroads Wind Indiana Crossroads Wind owns and operates 302 MW of nameplate capacity wind generation assets. NIPSCO and the tax equity partner made cash contributions in December 2021 per the equity capital contribution agreement. NIPSCO also assumed an obligation to the developer of the wind generation assets representing the remaining economic interest, which comes due in 2023. From the contributed funds, Indiana Crossroads Wind paid $233.0 million and zero to the developer of the wind generation assets as of December 31, 2021 and 2020, respectively. The developer of the facility is not a partner in the joint venture for federal income tax purposes and does not receive any share of earnings, tax attributes, or cash flows of Indiana Crossroads Wind. The following table displays the Noncontrolling interest in consolidated subsidiaries included in the Consolidated Balance Sheets: (in millions) December 31, 2021 December 31, 2020 Rosewater $ 88.2 $ 85.6 Indiana Crossroads Wind 237.4 — Total $ 325.6 $ 85.6 The following table displays the Net income (loss) attributable to noncontrolling interest included in the Statements of Consolidated Income (Loss) for the years ended December 31: (in millions) 2021 2020 2019 Rosewater $ (4.2) $ 3.4 $ — Indiana Crossroads Wind 8.1 — — Total $ 3.9 $ 3.4 $ — The following table displays the contributions associated with each VIE: (in millions) December 31, 2021 December 31, 2020 Rosewater Indiana Crossroads Wind Rosewater Indiana Crossroads Wind NIPSCO Cash Contribution $ 0.1 $ 2.7 $ 0.7 $ — Tax Equity Partner Cash Contribution 7.5 237.6 86.1 — NIPSCO's Obligation to Developer (1) 6.0 271.5 69.7 — Total Contributions $ 13.6 $ 511.8 $ 156.5 $ — (1) Included in "Other noncurrent liabilities" in the Consolidated Balance Sheets We did not provide any financial or other support during the year that was not previously contractually required, nor do we expect to provide such support in the future. Our Consolidated Balance Sheets included the following assets and liabilities associated with VIEs. (in millions) December 31, 2021 December 31, 2020 Rosewater Indiana Crossroads Wind Rosewater Indiana Crossroads Wind Net Property, Plant and Equipment $ 170.1 $ 525.8 $ 175.6 $ — Current assets 6.2 8.1 1.7 — Total assets (1) 176.3 533.9 177.3 — Current liabilities 2.5 7.5 15.3 — Asset retirement obligations 5.7 14.8 5.5 — Other noncurrent liabilities — — 0.1 — Total liabilities $ 8.2 $ 22.3 $ 20.9 $ — (1) The assets of Rosewater and Indiana Crossroads represent assets of a consolidated VIE that can be used only to settle obligations of the respective consolidated VIE. The creditors of the liabilities of Rosewater and Indiana Crossroads do not have recourse to the general credit of the primary beneficiary.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The calculations of basic and diluted EPS are based on the weighted average number of shares of common stock and potential common stock outstanding during the period. For the purposes of determining diluted EPS, the shares underlying the purchase contracts included within the Equity Units were included in the calculation of potential common stock outstanding for the year ended December 31, 2021 using the if-converted method under US GAAP. This method assumes conversion at the beginning of the reporting period, or at time of issuance, if later. For the purchase contracts, the number of shares of our common stock that would be issuable at the end of each reporting period will be reflected in the denominator of our diluted EPS calculation. If the stock price falls below the initial reference price of $24.51, subject to anti-dilution adjustments, the number of shares of our common stock used in calculating diluted EPS will be the maximum number of shares per the contract as described in Note 13, "Equity." Conversely, if the stock price is above the initial reference price of $24.51, subject to anti-dilution adjustments, a variable number of shares of our common stock will be used in calculating diluted EPS. A numerator adjustment was reflected in the calculation of diluted EPS for interest expense incurred in 2021, net of tax, related to the purchase contracts. The shares underlying the Series C Mandatory Convertible Preferred Stock included within the Equity Units are contingently convertible as the conversion is contingent on a successful remarketing as described in Note 13, "Equity." Contingently convertible shares where conversion is not tied to a market price trigger are excluded from the calculation of diluted EPS until such time as the contingency has been resolved under the if-converted method. As of December 31, 2021, the contingency was not resolved and thus no shares were reflected in the denominator in the calculation of diluted EPS for the year ended December 31, 2021. Diluted EPS also includes the incremental effects of the various long-term incentive compensation plans and the open ATM forward agreements during the period under the treasury stock method when the impact would be dilutive. Refer to Note 13, "Equity," for more information on our ATM forward agreements. For the year ended December 31, 2020, we had a net loss on the Statements of Consolidated Income (Loss) during the period, and any potentially dilutive shares would have had an anti-dilutive impact on EPS. The following table presents the calculation of our basic and diluted EPS: Year Ended December 31, (in millions, except per share amounts) 2021 2020 2019 Numerator: Net Income (Loss) Available to Common Shareholders - Basic $ 529.8 $ (72.7) $ 328.0 Dilutive effect of Equity Units 1.6 — — Net Income (Loss) Available to Common Shareholders - Diluted $ 531.4 $ (72.7) $ 328.0 Denominator: Average common shares outstanding - Basic 393.6 384.3 374.6 Dilutive potential common shares: Equity Units 22.0 — — Shares contingently issuable under employee stock plans 0.8 — 0.9 Shares restricted under employee stock plans 0.3 — 0.2 ATM Forward agreements 0.6 — 0.3 Average Common Shares - Diluted 417.3 384.3 376.0 Earnings per common share: Basic $ 1.35 $ (0.19) $ 0.88 Diluted $ 1.27 $ (0.19) $ 0.87

Property, Plant And Equipment

Property, Plant And Equipment	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Property, Plant And Equipment	Property, Plant and Equipment Our property, plant and equipment on the Consolidated Balance Sheets are classified as follows: At December 31, (in millions) 2021 2020 Property, Plant and Equipment Gas Distribution Utility (1) $ 15,240.6 $ 14,010.2 Electric Utility (1) 6,754.9 6,478.0 Corporate 217.8 197.3 Construction Work in Process 808.0 572.6 Renewable Generation Assets (2) 702.4 175.7 Non-Utility and Other (3) 1,447.6 2,746.1 Total Property, Plant and Equipment $ 25,171.3 $ 24,179.9 Accumulated Depreciation and Amortization Gas Distribution Utility (1) $ (3,490.2) $ (3,292.9) Electric Utility (1) (2,433.1) (2,305.0) Corporate (132.2) (109.3) Renewable Generation Assets (2) (6.5) (0.1) Non-Utility and Other (3) (1,227.5) (1,853.1) Total Accumulated Depreciation and Amortization $ (7,289.5) $ (7,560.4) Net Property, Plant and Equipment $ 17,881.8 $ 16,619.5 (1) NIPSCO’s common utility plant and associated accumulated depreciation and amortization are allocated between Gas Distribution Utility and Electric Utility Property, Plant and Equipment. (2) Our renewable generation assets are part of our electric segment and represent Non-Utility Property, owned and operated by joint ventures between NIPSCO and unrelated tax equity partners, and depreciated straight-line over 30 years. Refer to Note 4, "Variable Interest Entities," for additional information. (3) Non-Utility and Other as of December 31, 2020 includes net book value of four coal units totaling $903.8 million related to R.M. Schahfer Generating Station. Two of the four units were subsequently retired in 2021 and reclassified to current and long-term Regulatory Assets. Depreciation expense for the remaining net book value continues to be recorded at the composite depreciation rate approved by the IURC. As of December 31, 2021, Non-Utility and Other includes a net book value of $201.5 million related to the units not yet retired. On October 1, 2021, NIPSCO retired R.M. Schahfer Generating Station Units 14 and 15. The net book value of the retired units was reclassified from "Net Property, Plant and Equipment," to current and long-term ''Regulatory Assets.'' The estimated net book value of R.M. Schahfer Generating Station's coal Units 14 and 15 and other associated plant retired was approximately $600.0 million. See Note 9, "Regulatory Matters," for additional details regarding the recovery of the regulatory assets associated with retired generating stations. The weighted average depreciation provisions for utility plant, as a percentage of the original cost, for the periods ended December 31, 2021, 2020 and 2019 were as follows: 2021 2020 2019 Electric Operations (1) 3.4 % 3.4 % 2.8 % Gas Distribution Operations 2.2 % 2.3 % 2.5 % (1) Increased rate beginning in 2020 primarily attributable to higher depreciation rates from the recent rate case proceeding. We recognized depreciation expense of $672.1 million, $655.6 million and $612.2 million for the years ended 2021, 2020 and 2019, respectively. The 2021 depreciation expense amount includes a $5.3 million credit related to the regulatory deferral of income (loss) associated with our joint ventures, which is not included in current rates. See Note 9, "Regulatory Matters," for additional details. Amortization of on-premise Software Costs. We amortized $49.4 million, $56.7 million and $55.5 million in 2021, 2020 and 2019, respectively, related to software recorded as intangible assets. Our unamortized software balance was $181.8 million and $136.4 million at December 31, 2021 and 2020, respectively.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill And Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill. Substantially all of our goodwill relates to the excess of cost over the fair value of the net assets acquired in the Columbia acquisition on November 1, 2000. Our goodwill balance was $1,485.9 million as of December 31, 2021 and 2020. All our goodwill has been allocated to our Gas Distribution Operations segment. For our annual goodwill impairment analysis performed as of May 1, 2021, we completed a qualitative "step 0" assessment and determined that it was more likely than not that the estimated fair value of the reporting unit substantially exceeded the related carrying value of our reporting unit. For this test, we assessed various assumptions, events and circumstances that would have affected the estimated fair value of the reporting units as compared to their baseline May 1, 2020 "step 1" fair value measurement. Columbia of Massachusetts was not considered to be a reporting unit for May 1, 2020 fair value measurement as the goodwill balance had been reduced to zero as of December 31, 2019. During the fourth quarter of 2019, in connection with the preparation of the year-end financial statements, we assessed the matters related to the then proposed sale of the Massachusetts Business and determined a new impairment analysis was required for our Columbia of Massachusetts reporting unit. Fair value of this reporting unit was determined based on a weighting of income and market approaches. The income approach calculated discounted cash flows using updated cash flow projections, discount rates and return on equity assumptions. The market approach applied a combination of comparable company multiples and comparable transactions and used the most recent cash flow projections. The 2019 year-end impairment analysis indicated that the fair value of the Columbia of Massachusetts reporting unit was below its carrying value. As a result, we reduced the Columbia of Massachusetts reporting unit goodwill balance to zero and recognized a goodwill impairment charge totaling $204.8 million, which was non-deductible for tax purposes. Intangible and Other Long-Lived Assets Impairment. Prior to December 31, 2019, our intangible assets, apart from goodwill, consisted of franchise rights identified as part of the purchase price allocations associated with the acquisition in February 1999 of Columbia of Massachusetts. During the fourth quarter of 2019, in connection with the preparation of the year-end financial statements, we assessed the changes in circumstances that occurred during the quarter to determine if it was more likely than not that the fair value of our long-lived assets (including franchise rights) were below their carrying amount. As a result, we performed a year-end impairment test of our held and used long-lived assets in which we compared the book value of the Columbia of Massachusetts asset group to its undiscounted future cash flow and determined the carrying value of the asset group was not recoverable. We estimated the fair value of the Columbia of Massachusetts asset group using a weighting of income and market approaches and determined that the fair value was less than the carrying value. The resulting impairment was allocated to reduce the entire franchise rights book value to its fair value of zero, which resulted in an impairment charge totaling $209.7 million recorded in the Gas Distribution Operations segment during the year ended December 31, 2019. As of December 31, 2021 and 2020, the carrying amount of the franchise rights was zero. We recorded zero amortization expense in 2021 and 2020 and $11.0 million in 2019 related to our franchise rights intangible asset.

Asset Retirement Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2021
Asset Retirement Obligation [Abstract]
Asset Retirement Obligations	Asset Retirement ObligationsWe have recognized asset retirement obligations associated with various legal obligations including costs to remove and dispose of certain construction materials located within many of our facilities (including our joint venture facilities), certain costs to retire pipeline, removal costs for certain underground storage tanks, removal of certain pipelines known to contain PCB contamination, closure costs for certain sites including ash ponds, solid waste management units and a landfill, as well as some other nominal asset retirement obligations. We also have an obligation associated with the decommissioning of our two hydro facilities located in Indiana. These hydro facilities have an indeterminate life, and as such, no asset retirement obligation has been recorded. Changes in our liability for asset retirement obligations for the years 2021 and 2020 are presented in the table below: (in millions) 2021 2020 Beginning Balance $ 495.6 $ 416.9 Accretion recorded as a regulatory asset/liability 16.0 17.3 Additions 23.2 5.5 Settlements (11.2) (13.9) Change in estimated cash flows (11.2) 86.0 (1) Other — (16.2) (2) Ending Balance $ 512.4 $ 495.6 (1) The change in estimated cash flows for 2020 is primarily attributed to revisions to the estimated costs associated with refining the CCR compliance plan, changes in estimated costs for electric generating stations and the changes in estimated costs for retirement of gas mains. See Note 19-E, "Environmental Matters," for additional information on CCRs. (2) Represents the Columbia of Massachusetts Asset Retirement Obligations that were included in the sale of the Massachusetts Business that occurred on October 9, 2020. Certain non-legal costs of removal that have been, and continue to be, included in depreciation rates and collected in the customer rates of the rate-regulated subsidiaries are classified as "Regulatory liabilities" on the Consolidated Balance Sheets.

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2021
Regulatory Assets and Liabilities Disclosure [Abstract]
Regulatory Matters	Regulatory Matters Regulatory Assets and Liabilities We follow the accounting and reporting requirements of ASC Topic 980, which provides that regulated entities account for and report assets and liabilities consistent with the economic effect of regulatory rate-making procedures when the rates established are designed to recover the costs of providing the regulated service and it is probable that such rates will be charged and collected from customers. Certain expenses and credits subject to utility regulation or rate determination normally reflected in income or expense are deferred on the balance sheet and are recognized in the income statement as the related amounts are included in customer rates and recovered from or refunded to customers. We assess the probability of collection for all of our regulatory assets each period. Regulatory assets were comprised of the following items: At December 31, (in millions) 2021 2020 Regulatory Assets Unrecognized pension and other postretirement benefit costs (see Note 12) $ 512.1 $ 583.3 Deferred pension and other postretirement benefit costs (see Note 12) 74.8 72.4 Environmental costs (see Note 19-E) 45.8 56.6 Regulatory effects of accounting for income taxes (see Note 1-N and Note 11) 194.8 194.5 Under-recovered gas and fuel costs (see Note 1-J) 73.6 8.0 Depreciation 177.5 192.6 Post-in-service carrying charges 237.9 228.6 Safety activity costs 171.9 146.0 DSM programs 39.2 37.8 Retired coal generating stations 803.9 204.7 Losses on commodity price risk programs (See Note 10) 9.6 54.7 Deferred property taxes 65.1 62.9 Renewable energy investments (See Note 1-S and Note 4) 18.5 — Other 67.5 88.4 Total Regulatory Assets $ 2,492.2 $ 1,930.5 Less: Current Portion 206.2 135.7 Total Noncurrent Regulatory Assets $ 2,286.0 $ 1,794.8 Regulatory liabilities were comprised of the following items: At December 31, (in millions) 2021 2020 Regulatory Liabilities Over-recovered gas and fuel costs (see Note 1-J) $ 5.4 $ 47.8 Cost of removal (see Note 8) 749.5 775.2 Regulatory effects of accounting for income taxes (see Note 1-N and Note 11) 1,040.8 1,105.1 Deferred pension and other postretirement benefit costs (see Note 12) 75.9 69.5 Gains on commodity price risk programs (See Note 10) 34.2 14.0 Other 74.2 53.9 Total Regulatory Liabilities $ 1,980.0 $ 2,065.5 Less: Current Portion 137.4 161.3 Total Noncurrent Regulatory Liabilities $ 1,842.6 $ 1,904.2 Regulatory assets, including under-recovered gas and fuel costs and depreciation, of approximately $1,207.0 million and $1,260.6 million as of December 31, 2021 and 2020, respectively, are not earning a return on investment. These costs are recovered over a remaining life, the longest of which is 48 years. Assets: Unrecognized pension and other postretirement benefit costs. Represents the deferred other comprehensive income or loss of the actuarial gains or losses and the prior service costs or credits that arise during the period but that are not immediately recognized as components of net periodic benefit costs by certain subsidiaries that will ultimately be recovered through base rates. Deferred pension and other postretirement benefit costs. Primarily relates to the difference between defined benefit plan expense recorded by certain subsidiaries due to regulatory orders and the corresponding expense that would otherwise be recorded in accordance with GAAP. The majority of these amounts are driven by Columbia of Ohio. The timeframe for the recovery of these costs are expected to be addressed in our base rate case, and the costs are expected to be collected through future base rates, revenue riders or tracking mechanisms. Environmental costs. Includes certain recoverable costs related to gas plant sites, disposal sites or other sites onto which material may have migrated, the recovery of which is to be addressed in future base rates, billing riders or tracking mechanisms of certain of our subsidiaries. Regulatory effects of accounting for income taxes. Represents the deferral and under collection of deferred taxes in the rate making process. Under-recovered gas and fuel costs. Represents the difference between the costs of gas and fuel and the recovery of such costs in revenue and is used to adjust future billings for such deferrals on a basis consistent with applicable state-approved tariff provisions. Recovery of these costs is achieved through tracking mechanisms. Depreciation. Represents differences between depreciation expense incurred on a GAAP basis and that prescribed through regulatory order. The majority of this balance is driven by Columbia of Ohio's IRP and CEP deferrals. Recovery of these amounts is approved annually through the related riders. Post-in-service carrying charges. Represents deferred debt-based carrying charges incurred on certain assets placed into service but not yet included in customer rates. The majority of this balance is driven by Columbia of Ohio's IRP and CEP deferrals. Safety activity costs. Represents the difference between costs incurred by certain of our subsidiaries in eligible safety programs in compliance with PHMSA regulations in excess of those being recovered in rates. DSM programs. Represents costs associated with Gas Distribution Operations and Electric Operations segments' energy efficiency and conservation programs. Costs are recovered through tracking mechanisms. Retired coal generating stations. Represents the net book value of Units 7 and 8 of Bailly Generating Station that was retired during 2018 and the net book value of Units 14 and 15 of R.M. Schahfer Generating Station retired in 2021. These amounts are currently being amortized at a rate consistent with their inclusion in customer rates. The December 2019 NIPSCO electric rate case order allows for the recovery of, and on, the net book value of the stations by the end of 2032 and implements a revenue credit for the retired units. The credit is based on the difference between the net book value of Units 14 and 15 upon retirement and the last base rate case proceeding. The credit will be reset when new base rates are determined. See Note 6, "Property, Plant and Equipment," for further details. Losses on commodity price risk programs . Represents the unrealized losses related to certain of our subsidiary's commodity price risk programs. These programs help to protect against the volatility of commodity prices and these amounts are collected from customers through their inclusion in customer rates. Deferred property taxes . Represents the deferral and under collection of property taxes in the rate making process for Columbia of Ohio and is driven by the IRP and CEP deferrals. Renewable energy investments. Represents the regulatory deferral of certain amounts representing the timing difference between the profit earned from the joint ventures and the amount included in regulated rates to recover our approved investments in consolidated joint ventures. These amounts will be collected through base rates over the life of the renewable generating assets to which they relate. Refer to Note 1-S, "VIEs and Allocation of Earnings," for additional information. Renewable energy formation and developer costs are also included in this regulatory asset. Liabilities: Over-recovered gas and fuel costs. Represents the difference between the cost of gas and fuel and the recovery of such costs in revenues and is the basis to adjust future billings for such refunds on a basis consistent with applicable state-approved tariff provisions. Refunding of these revenues is achieved through tracking mechanisms. Cost of removal. Represents anticipated costs of removal for utility assets that have been collected through depreciation rates for future costs to be incurred. Regulatory effects of accounting for income taxes. Represents amounts owed to customers for deferred taxes collected at a higher rate than the current statutory rates and liabilities associated with accelerated tax deductions owed to customers. Balance includes excess deferred taxes recorded upon implementation of the TCJA in December 2017, net of amounts amortized through 2021. Deferred pension and other postretirement benefit costs. Primarily represents cash contributions in excess of postretirement benefit expense that is deferred by certain subsidiaries. Gains on commodity price risk programs . Represents the unrealized gains related to certain of our subsidiary's commodity price risk programs. These programs help to protect against the volatility of commodity prices, and these amounts are passed back to customers through their inclusion in customer rates. COVID-19 Regulatory Filings In response to COVID-19, we received approvals or directives from the regulatory commissions in the states in which we operate. The ongoing impacts of these approvals or directives are described in the table below: Jurisdiction Moratorium in Place? Regulatory Asset balance as of December 31, 2021 (in millions) Regulatory Asset balance as of December 31, 2020 (in millions) Deferred COVID-19 Costs Columbia of Ohio No $ 2.1 $ 2.0 Incremental operation and maintenance expenses NIPSCO No $ 2.2 $ 9.2 Incremental bad debt expense and the costs to implement the requirements of the COVID-19 related order Columbia of Pennsylvania No $ 5.2 $ 5.4 Incremental bad debt expense incurred from March 13, 2020 through December 29, 2021, above levels currently in rates Columbia of Virginia No $ 1.5 $ — Incremental incurred costs (including incremental bad debt expense), subject to an earnings test review Columbia of Maryland No $ 0.9 $ 0.7 Incremental costs (including incremental bad debt expense) incurred to ensure that customers have essential utility service during the state of emergency in Maryland. Such incremental costs must be offset by any benefit received in connection with the pandemic The Pennsylvania PUC adopted an order on March 11, 2021, and subsequently reaffirmed their stance in a June 23, 2021 order, which lifted its prior pandemic-related moratorium on service terminations for non-payments of utility bills beginning April 1, 2021. Pursuant to that order, Pennsylvania utilities are required to offer payment plans on billing arrearages, with the length of such payment plans depending on a customer's income level. Pursuant to a subsequent order, Pennsylvania utilities were no longer required to offer these extended pandemic-related payment arrangements to customers in arrears as of October 1, 2021.On December 16, 2021, CPA received a final order approving its 2021 base rate case, which includes a provision to discontinue the deferral of COVID-19 uncollectible accounts as of December 29, 2021 and begin recovery of amounts deferred as of 12/31/2020 over a five year period beginning on January 1, 2022. For Columbia of Virginia, the moratorium on non-residential disconnections ended on October 6, 2020, and the moratorium on residential disconnections and late payment fees ended on August 30, 2021. Legislative and regulatory requirements extending COVID-19 payment plans between 6 and 24 months remain in place. In connection with the Maryland Relief Act and the order issued by the PSC of Maryland on June 15, 2021, Columbia of Maryland received approximately $0.8 million of assistance that was applied to customer accounts in August 2021. As such, all termination moratoriums were lifted and normal collections procedures resumed on November 1, 2021. Unless otherwise noted above, all other pandemic-related regulatory actions have expired or been lifted.

Risk Management Activities

Risk Management Activities	12 Months Ended
	Dec. 31, 2021
Risk Management Activities [Abstract]
Risk Management Activities	Risk Management Activities We are exposed to certain risks related to our ongoing business operations; namely commodity price risk and interest rate risk. We recognize that the prudent and selective use of derivatives may help to lower our cost of debt capital, manage interest rate exposure and limit volatility in the price of natural gas. Risk management assets and liabilities on our derivatives are presented on the Consolidated Balance Sheets as shown below: December 31, 2021 December 31, 2020 (in millions) Assets Liabilities Assets Liabilities Current (1) Derivatives designated as hedging instruments $ — $ 136.4 $ — $ 70.9 Derivatives not designated as hedging instruments 10.6 0.4 10.4 7.3 Total $ 10.6 $ 136.8 $ 10.4 $ 78.2 Noncurrent (2) Derivatives designated as hedging instruments $ — $ — $ — $ 99.5 Derivatives not designated as hedging instruments 13.8 7.4 2.8 45.1 Total $ 13.8 $ 7.4 $ 2.8 $ 144.6 (1) Presented in "Prepayments and other" and "Other accruals", respectively, on the Consolidated Balance Sheets. (2) Presented in "Deferred charges and other" and "Other noncurrent liabilities", respectively, on the Consolidated Balance Sheets. Derivatives Not Designated as Hedging Instruments C ommodity price risk management. We, along with our utility customers, are exposed to variability in cash flows associated with natural gas purchases and volatility in natural gas prices. We purchase natural gas for sale and delivery to our retail, commercial and industrial customers, and for most customers the variability in the market price of gas is passed through in their rates. Some of our utility subsidiaries offer programs whereby variability in the market price of gas is assumed by the respective utility. The objective of our commodity price risk programs is to mitigate the gas cost variability, for us or on behalf of our customers, associated with natural gas purchases or sales by economically hedging the various gas cost components using a combination of futures, options, forwards or other derivative contracts. At December 31, 2021, we had 124.5 MMDth of net energy derivative volumes outstanding related to our natural gas hedges. NIPSCO has received IURC approval to lock in a fixed price for its natural gas customers using long-term forward purchase instruments and is limited to 20% of NIPSCO’s average annual GCA purchase volume. As of December 31, 2021, the remaining terms of these instruments range from one six All gains and losses on these derivative contracts are deferred as regulatory liabilities or assets and are remitted to or collected from customers through NIPSCO’s quarterly GCA and FAC mechanisms, respectively. These instruments are not designated as accounting hedges. Refer to Note 9, "Regulatory Matters," for additional information. Derivatives Designated as Hedging Instruments Interest rate risk management. As of December 31, 2021, we have two forward-starting interest rate swaps with an aggregate notional value totaling $500.0 million to hedge the variability in cash flows attributable to changes in the benchmark interest rate associated with forecasted debt issuances. These interest rate swaps are designated as cash flow hedges. Cash flow hedges included in Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheets were: (in millions) AOCI (1) Amounts Expected to be Reclassified to Earnings During the Next 12 Months (1) Maximum Term Interest Rate $ 25.4 0.8 371 months (1) All amounts are net of tax. The actual amounts reclassified from Accumulated Other Comprehensive Income (Loss) to Net Income can differ from the estimate above due to market price changes. The gains and losses related to these swaps are recorded to AOCI. Upon issuance, we amortize the gains and losses over the life of the debt associated with these swaps as we recognize interest expense. These amounts are immaterial in 2021, 2020 and 2019 and are recorded in "Interest expense, net" on the Statements of Consolidated Income (Loss). If it becomes probable that a hedged forecasted transaction will no longer occur, the accumulated gains or losses on the derivative will be recognized currently in "Other, net" in the Statements of Consolidated Income (Loss). There were no amounts excluded from effectiveness testing for derivatives in cash flow hedging relationships at December 31, 2021, 2020 and 2019. Our derivative instruments measured at fair value as of December 31, 2021 and 2020 do not contain any credit-risk-related contingent features. Cash flows for derivative financial instruments are generally classified in cash flows from operating activities.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income Tax Expense. The components of income tax expense (benefit) were as follows: Year Ended December 31, (in millions) 2021 2020 2019 Income Taxes Current Federal $ (0.1) $ 0.2 $ — State 6.0 11.7 5.2 Total Current 5.9 11.9 5.2 Deferred Federal 99.2 (0.4) 110.7 State 13.8 (27.4) 9.0 Total Deferred 113.0 (27.8) 119.7 Deferred Investment Credits (1.1) (1.2) (1.4) Income Taxes $ 117.8 $ (17.1) $ 123.5 Statutory Rate Reconciliation. The following table represents a reconciliation of income tax expense at the statutory federal income tax rate to the actual income tax expense from continuing operations: Year Ended December 31, (in millions) 2021 2020 2019 Book income (loss) before income taxes $ 706.6 $ (31.3) $ 506.6 Tax expense (benefit) at statutory federal income tax rate 148.3 21.0 % (6.6) 21.0 % 106.5 21.0 % Increases (reductions) in taxes resulting from: State income taxes, net of federal income tax benefit 14.1 2.0 (11.7) 37.4 10.1 2.0 Amortization of regulatory liabilities (39.1) (5.5) (38.4) 122.7 (29.4) (5.8) Goodwill impairment — — — — 43.0 8.5 Fines and penalties — — 11.8 (37.7) 11.5 2.3 Charitable contribution carryover — — — — (2.5) (0.5) State regulatory proceedings — — — — (9.5) (1.9) Employee stock ownership plan dividends and other compensation (1.2) (0.2) (1.3) 4.2 (2.0) (0.4) Deferred taxes on TCJA regulatory liability divested — — 23.3 (74.5) — — Tax accrual adjustments (0.1) — 8.9 (28.4) — — Federal tax credits (2.1) (0.3) (2.5) 8.0 — — Other adjustments (2.1) (0.3) (0.6) 1.9 (4.2) (0.8) Income Taxes $ 117.8 16.7 % $ (17.1) 54.6 % $ 123.5 24.4 % The difference in tax expense year-over-year has a relative impact on the effective tax rate proportional to pretax income or loss. The 37.9% decrease in effective tax rate in 2021 versus 2020 was primarily the result of higher pre-tax income, state jurisdictional mix of pre-tax income in 2021 tax effected at statutory tax rates and increased amortization of excess deferred federal income taxes in 2021 compared to 2020. These items were offset by decreased deferred tax expense recognized on the sale of Columbia of Massachusetts' regulatory liability in 2020, established due to TCJA in 2017, that would have otherwise been recognized over the amortization period, 2020 non-deductible penalties and valuation allowance related to Columbia of Massachusetts and 2020 one-time tax accrual adjustments. The 30.2% increase in effective tax rate in 2020 versus 2019 was primarily the result of lower pre-tax income, state jurisdictional mix of pre-tax loss in 2020 tax effected at statutory tax rates and increased amortization of excess deferred federal income taxes in 2020 compared to 2019. These items were offset by increased deferred tax expense recognized on the sale of Columbia of Massachusetts' regulatory liability, established due to TCJA in 2017, that would have otherwise been recognized over the amortization period, non-deductible penalties and non-cash impairment of goodwill related to Columbia of Massachusetts in 2019 (see Note 7, "Goodwill and Other Intangible Assets" for additional information), and one-time tax accrual adjustments. Net Deferred Income Tax Liability Components. Deferred income taxes result from temporary differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities. The principal components of our net deferred tax liability were as follows: At December 31, (in millions) 2021 2020 Deferred tax liabilities Accelerated depreciation and other property differences $ 2,454.4 $ 2,339.3 Other regulatory assets 308.6 331.8 Total Deferred Tax Liabilities 2,763.0 2,671.1 Deferred tax assets Other regulatory liabilities and deferred investment tax credits (including TCJA) 284.7 287.8 Pension and other postretirement/postemployment benefits 104.8 118.1 Net operating loss carryforward and AMT credit carryforward 545.9 608.5 Environmental liabilities 22.2 22.6 Other accrued liabilities 42.1 41.5 Other, net 111.7 128.4 Total Deferred Tax Assets 1,111.4 1,206.9 Valuation Allowance (7.8) (6.4) Net Deferred Tax Assets 1,103.6 1,200.5 Net Deferred Tax Liabilities $ 1,659.4 $ 1,470.6 At December 31, 2021, we have federal net operating loss carryforwards of $464.4 million (tax effected). The federal net operating loss carryforwards are available to offset taxable income and will begin to expire in 2036. We believe it is more likely than not that we will realize the benefit from the federal net operating loss carryforwards. We also have $73.7 million (tax effected, net of federal benefit) of state net operating loss carryforwards. Depending on the jurisdiction in which the state net operating loss was generated, the carryforwards will begin to expire in 2028. We believe it is more likely than not that a portion of the benefit from certain state NOL carryforwards will not be realized. In recognition of this risk, we have provided a valuation allowance of $7.8 million (net) on the deferred tax assets related to sale of Massachusetts Business assets reflected in the state net operating loss carryforward presented above. Unrecognized Tax Benefits. A reconciliation of the beginning and ending amounts of unrecognized tax benefits is as follows: At December 31, 2021, (in millions) 2021 2020 2019 Opening Balance $ 21.7 $ 23.2 $ 1.2 Gross decreases - tax positions in prior period — (1.5) (0.6) Gross increases - current period tax positions — — 22.6 Ending Balance $ 21.7 $ 21.7 $ 23.2 Offset for net operating loss carryforwards (21.7) (21.7) (22.6) Balance, Less Net Operating Loss Carryforwards $ — $ — $ 0.6 We present accrued interest on unrecognized tax benefits, accrued interest on other income tax liabilities and tax penalties in "Income Taxes" on our Statements of Consolidated Income (Loss). Interest expense recorded on unrecognized tax benefits and other income tax liabilities was immaterial for all periods presented. There were no accruals for penalties recorded in the Statements of Consolidated Income (Loss) for the years ended December 31, 2021, 2020 and 2019, and there were no balances for accrued penalties recorded on the Consolidated Balance Sheets as of December 31, 2021 and 2020. We are subject to income taxation in the United States and various state jurisdictions, primarily Indiana, Pennsylvania, Kentucky, Massachusetts, Maryland and Virginia. We participate in the IRS CAP, which provides the opportunity to resolve tax matters with the IRS before filing each year's consolidated federal income tax return. As of December 31, 2021, tax years through 2020 have been audited and are effectively closed to further assessment. The audit of tax year 2021 under the CAP program is expected to be completed in 2022. The statute of limitations in each of the state jurisdictions in which we operate remains open between 3-4 years from the date the state income tax returns are filed. As of December 31, 2021, there were no state income tax audits in progress that would have a material impact on the consolidated financial statements.

Pension and Other Postretiremen

Pension and Other Postretirement Benefits	12 Months Ended
	Dec. 31, 2021
Pension and Other Postretirement Benefits Cost (Reversal of Cost) [Abstract]
Pension and Other Postretirement Benefits	Pension and Other Postretirement Benefits We provide defined contribution plans and noncontributory defined benefit retirement plans that cover certain of our employees. Benefits under the defined benefit retirement plans reflect the employees’ compensation, years of service and age at retirement. Additionally, we provide health care and life insurance benefits for certain retired employees. The majority of employees may become eligible for these benefits if they reach retirement age while working for us. The expected cost of such benefits is accrued during the employees’ years of service. Current rates of rate-regulated companies include postretirement benefit costs, including amortization of the regulatory assets that arose prior to inclusion of these costs in rates. For most plans, cash contributions are remitted to grantor trusts. Our Pension and Other Postretirement Benefit Plans’ Asset Management . The Board has delegated oversight of the pension and other postretirement benefit plans’ assets to the NiSource Benefits Committee (“the Committee”). The Committee has adopted investment policy statements for the pension and other postretirement benefit plans’ assets. For the pension plans, we employ a liability-driven investing strategy. A total return approach is utilized for the other postretirement benefit plans’ assets. A mix of diversified investments are used to maximize the long-term return of plan assets and hedge the liabilities at a prudent level of risk. The investment portfolio includes U.S. and non-U.S. equities, real estate, long-term and intermediate-term fixed income and alternative investments. Risk tolerance is established through careful consideration of plan liabilities, funded status, and asset class volatility. Investment risk is measured and monitored on an ongoing basis through quarterly investment portfolio reviews, annual liability measurements, and periodic asset/liability studies. In determining the expected long-term rate of return on plan assets, historical markets are studied, relationships between equities and fixed income are analyzed and current market factors, such as inflation and interest rates are evaluated with consideration of diversification and rebalancing. Our expected long-term rate of return on assets is based on assumptions regarding target asset allocations and corresponding long-term capital market assumptions for each asset class. The pension plans’ investment policy calls for a gradual reduction in the allocation of return-seeking assets (equities, real estate and private equity) and a corresponding increase in the allocation of liability-hedging assets (fixed income) as the funded status of the plans’ increase. As of December 31, 2021 and December 31, 2020, the acceptable minimum and maximum ranges established by the policy for the pension and other postretirement benefit plans are as follows: December 31, 2021 Defined Benefit Pension Plan Postretirement Benefit Plan Asset Category Minimum Maximum Minimum Maximum Domestic Equities 7% 27% 0% 55% International Equities 3% 13% 0% 25% Fixed Income 69% 81% 20% 100% Real Estate 0% 3% 0% 0% Private Equity 0% 3% 0% 0% Short-Term Investments 0% 10% 0% 10% December 31, 2020 Defined Benefit Pension Plan Postretirement Benefit Plan Asset Category Minimum Maximum Minimum Maximum Domestic Equities 12% 32% 0% 55% International Equities 6% 16% 0% 25% Fixed Income 59% 71% 20% 100% Real Estate 0% 7% 0% 0% Private Equity 0% 5% 0% 0% Short-Term Investments 0% 10% 0% 10% The actual Pension Plan and Postretirement Plan Asset Mix at December 31, 2021 and December 31, 2020 are as follows: Defined Benefit Pension Assets (1) December 31, Postretirement December 31, Asset Class (in millions) Asset Value % of Total Assets Asset Value % of Total Assets Domestic Equities $ 324.3 16.4 % $ 118.6 40.4 % International Equities 150.9 7.6 % 50.5 17.2 % Fixed Income 1,382.3 69.7 % 118.8 40.4 % Real Estate 37.2 1.9 % — — Cash/Other 87.0 4.4 % 5.8 2.0 % Total $ 1,981.7 100.0 % $ 293.7 100.0 % Defined Benefit Pension Assets (1) December 31, Postretirement Benefit Plan Assets December 31, Asset Class (in millions) Asset Value % of Total Assets Asset Value % of Total Assets Domestic Equities $ 446.3 21.0 % $ 108.8 38.0 % International Equities 230.1 10.9 % 48.2 16.8 % Fixed Income 1,291.2 61.0 % 122.0 42.6 % Real Estate 52.9 2.5 % — — Cash/Other 97.2 4.6 % 7.4 2.6 % Total $ 2,117.7 100.0 % $ 286.4 100.0 % (1) Total includes accrued dividends and pending traders with brokers. The categorization of investments into the asset classes in the tables above are based on definitions established by the Committee. Fair Value Measurements. The following table sets forth, by level within the fair value hierarchy, the pension and other postretirement benefits investment assets at fair value as of December 31, 2021 and 2020. Assets are classified in their entirety based on the observability of inputs used in determining the fair value measurement. There were no investment assets in the pension and other postretirement benefits trusts classified within Level 3 for the years ended December 31, 2021 and 2020. We use the following valuation techniques to determine fair value. For the year ended December 31, 2021, there were no significant changes to valuation techniques to determine the fair value of our pension and other postretirement benefits' assets. Level 1 Measurements Most common and preferred stocks are traded in active markets on national and international securities exchanges and are valued at closing prices on the last business day of each period presented. Cash is stated at cost, which approximates fair value, with the exception of cash held in foreign currencies which fluctuates with changes in the exchange rates. Short-term bills and notes are priced based on quoted market values. Level 2 Measurements Most U.S. Government Agency obligations, mortgage/asset-backed securities, and corporate fixed income securities are generally valued by benchmarking model-derived prices to quoted market prices and trade data for identical or comparable securities. To the extent that quoted prices are not available, fair value is determined based on a valuation model that includes inputs such as interest rate yield curves and credit spreads. Securities traded in markets that are not considered active are valued based on quoted market prices, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency. Other fixed income includes futures and options which are priced on bid valuation or settlement pricing. Level 3 Measurements Investments with unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities are classified as level 3 investments. Not Classified Commingled funds, private equity limited partnerships and real estate partnerships are not classified within the fair value hierarchy. Instead, these assets are measured at estimated fair value using the net asset value per share of the investments. Commingled funds' underlying assets are principally marketable equity and fixed income securities. Units held in commingled funds are valued at the unit value as reported by the investment managers. Private equity and real estate funds invest in natural resources, commercial real estate and distressed real estate. The fair value of these investments is determined by reference to the funds’ underlying assets. Fair Value Measurements at December 31, 2021: (in millions) December 31, Quoted Prices in Active Markets for Significant Other Significant Pension plan assets: Cash $ 10.3 $ 9.7 $ 0.6 $ — Equity securities International equities 0.5 0.5 — — Fixed income securities Government 387.3 — 387.3 — Corporate 645.9 — 645.9 — Mutual Funds U.S. multi-strategy 128.4 128.4 — — International equities 38.7 38.7 — — Private equity limited partnerships (3) U.S. multi-strategy (1) 10.9 — — — International multi-strategy (2) 4.5 — — — Distressed opportunities 0.1 — — — Real estate (3) 37.2 — — — Commingled funds (3) Short-term money markets 55.0 — — — U.S. equities 195.9 — — — International equities 111.7 — — — Fixed income 349.1 — — — Pension plan assets subtotal 1,975.5 177.3 1,033.8 — Other postretirement benefit plan assets: Mutual funds U.S. multi-strategy 103.8 103.8 — — International equities 24.4 24.4 — — Fixed income 118.5 118.5 — — Commingled funds (3) Short-term money markets 5.8 — — — U.S. equities 14.8 — — — International equities 26.1 — — — Other postretirement benefit plan assets subtotal 293.4 246.7 — — Due to brokers, net (4) (1.8) — (1.8) — Receivables/payables 0.3 — 0.3 — Accrued income/dividends 8.0 8.0 — — Total pension and other postretirement benefit plan assets $ 2,275.4 $ 432.0 $ 1,032.3 $ — (1) This class includes limited partnerships/fund of funds that invest in a diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily inside the United States. (2) This class includes limited partnerships/fund of funds that invest a in diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily outside the United States. (3) This class of investments is measured at fair value using the net asset value per share and has not been classified in the fair value hierarchy. (4) This class represents pending trades with brokers. The table below sets forth a summary of unfunded commitments, redemption frequency and redemption notice periods for certain investments that are measured at fair value using the net asset value per share for the year ended December 31, 2021: (in millions) Fair Value Unfunded Commitments Redemption Frequency Redemption Notice Period Commingled Funds Short-term money markets $ 60.8 $ — Daily 1 day U.S. equities 210.7 — Daily 1 day - 5 days International equities 137.8 — Monthly 10 days-30 days Fixed income 349.1 — Daily 3 days Private Equity and Real Estate Limited Partnerships (1) 20.4 12.1 N/A N/A Total $ 778.8 $ 12.1 (1) Private equity and real estate limited partnerships typically call capital over a 3-5 year period and pay out distributions as the underlying investments are liquidated. The typical expected life of these limited partnerships is 0-15 years, and these investments typically cannot be redeemed prior to liquidation. Fair Value Measurements at December 31, 2020: (in millions) December 31, Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Significant Pension plan assets: Cash $ 11.9 $ 11.9 $ — $ — Equity securities U.S. equities 2.4 2.4 — — Fixed income securities Government 243.4 — 243.4 — Corporate 692.6 — 692.6 — Mutual Funds U.S. multi-strategy 161.3 161.3 — — International equities 55.4 55.4 — — Fixed income 0.1 0.1 — — Private equity limited partnerships (3) U.S. multi-strategy (1) 10.9 — — — International multi-strategy (2) 6.6 — — — Distressed opportunities 0.3 — — — Real Estate 52.9 — — — Commingled funds (3) Short-term money markets 78.8 — — — U.S. equities 279.7 — — — International equities 176.8 — — — Fixed income 337.6 — — — Pension plan assets subtotal 2,110.7 231.1 936.0 — Other postretirement benefit plan assets: Mutual funds U.S. multi-strategy 94.8 94.8 — — International equities 24.1 24.1 — — Fixed income 121.8 121.8 — — Commingled funds (3) Short-term money markets 7.6 — — — U.S. equities 14.0 — — — International equities 24.1 — — — Other postretirement benefit plan assets subtotal 286.4 240.7 — — Due to brokers, net (4) (1.6) — (1.6) — Accrued income/dividends 8.6 8.6 — — Total pension and other postretirement benefit plan assets $ 2,404.1 $ 480.4 $ 934.4 $ — (1) This class includes limited partnerships/fund of funds that invest in a diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily inside the United States. (2) This class includes limited partnerships/fund of funds that invest in diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily outside the United States. (3) This class of investments is measured at fair value using the net asset value per share and has not been classified in the fair value hierarchy. (4) This class represents pending trades with brokers. The table below sets forth a summary of unfunded commitments, redemption frequency and redemption notice periods for certain investments that are measured at fair value using the net asset value per share for the year ended December 31, 2020: (in millions) Fair Value Unfunded Commitments Redemption Frequency Redemption Notice Period Commingled Funds Short-term money markets $ 86.4 $ — Daily 1 day U.S. equities 293.7 — Monthly 1 day -5 days International equities 200.9 — Monthly 10 days - 30 days Fixed income 337.6 — Daily 3 days Private Equity and Real Estate Limited Partnerships (1) 22.7 12.1 N/A N/A Total $ 941.3 $ 12.1 (1) Private equity and real estate limited partnerships typically call capital over a 3-5 year period and pay out distributions as the underlying investments are liquidated. The typical expected life of these limited partnerships is 0-15 years, and these investments typically cannot be redeemed prior to liquidation. Our Pension and Other Postretirement Benefit Plans’ Funded Status and Related Disclosure . The following table provides a reconciliation of the plans’ funded status and amounts reflected in our Consolidated Balance Sheets at December 31 based on a December 31 measurement date: Pension Benefits Other Postretirement Benefits (in millions) 2021 2020 2021 2020 Change in projected benefit obligation (1) Benefit obligation at beginning of year $ 2,058.4 $ 2,130.5 $ 590.8 $ 576.5 Service cost 30.2 32.0 6.2 6.6 Interest cost 31.4 51.6 9.9 15.4 Plan participants’ contributions — — 4.2 4.1 Plan amendments — — 0.1 — Actuarial (gain) loss (2) (68.7) 140.1 (14.8) 24.8 Benefits paid (198.9) (174.5) (40.6) (37.0) Estimated benefits paid by incurred subsidy — — 0.4 0.4 Spinoff to Eversource — (121.3) — — Projected benefit obligation at end of year $ 1,852.4 $ 2,058.4 $ 556.2 $ 590.8 Change in plan assets Fair value of plan assets at beginning of year $ 2,117.7 $ 2,080.9 $ 286.4 $ 261.4 Actual return on plan assets 58.9 329.9 23.9 36.3 Employer contributions 4.0 2.9 19.8 21.6 Plan participants’ contributions — — 4.2 4.1 Benefits paid (198.9) (174.6) (40.6) (37.0) Spinoff to Eversource — (121.4) — — Fair value of plan assets at end of year $ 1,981.7 $ 2,117.7 $ 293.7 $ 286.4 Funded Status at end of year $ 129.3 $ 59.3 $ (262.5) $ (304.4) Amounts recognized in the statement of financial position consist of: Noncurrent assets 159.3 91.4 — — Current liabilities (2.8) (2.9) (1.0) (0.9) Noncurrent liabilities (27.2) (29.2) (261.5) (303.5) Net amount recognized at end of year (3) $ 129.3 $ 59.3 $ (262.5) $ (304.4) Amounts recognized in accumulated other comprehensive income or regulatory asset/liability (4) Unrecognized prior service credit $ 0.3 $ 0.3 $ (7.8) $ (10.1) Unrecognized actuarial loss 438.0 497.2 88.5 116.4 Net amount recognized at end of year $ 438.3 $ 497.5 $ 80.7 $ 106.3 (1) The change in benefit obligation for Pension Benefits represents the change in Projected Benefit Obligation while the change in benefit obligation for Other Postretirement Benefits represents the change in accumulated postretirement benefit obligation. (2) The pension actuarial gain was primarily driven by the increase in discount rate. The postretirement benefit gain was also primarily driven by an increase in discount rates. (3) We recognize our Consolidated Balance Sheets underfunded and overfunded status of our various defined benefit postretirement plans, measured as the difference between the fair value of the plan assets and the benefit obligation. (4) We determined that for certain rate-regulated subsidiaries the future recovery of pension and other postretirement benefits costs is probable. These rate-regulated subsidiaries recorded regulatory assets and liabilities of $512.1 million and zero, respectively, as of December 31, 2021, and $583.3 million and zero, respectively, as of December 31, 2020 that would otherwise have been recorded to accumulated other comprehensive loss. Our accumulated benefit obligation for our pension plans was $1,834.4 million and $2,036.8 million as of December 31, 2021 and 2020, respectively. The accumulated benefit obligation at each date is the actuarial present value of benefits attributed by the pension benefit formula to employee service rendered prior to that date and based on current and past compensation levels. The accumulated benefit obligation differs from the projected benefit obligation disclosed in the table above in that it includes no assumptions about future compensation levels. We are required to reflect the funded status of our pension and postretirement benefit plans on the Consolidated Balance Sheet. The funded status of the plans is measured as the difference between the plan assets' fair value and the projected benefit obligation. We present the noncurrent aggregate of all underfunded plans within "Accrued liability for postretirement and postemployment benefits." The portion of the amount by which the actuarial present value of benefits included in the projected benefit obligation exceeds the fair value of plan assets, payable in the next 12 months, is reflected in "Accrued compensation and other benefits." We present the aggregate of all overfunded plans within "Deferred charges and other." Information for pension plans with a projected benefit obligation in excess of plan assets: December 31, 2021 2020 Accumulated Benefit Obligation $ 30.0 $ 32.1 Funded Status Projected Benefit Obligation 30.0 32.1 Fair Value of Plan Assets — — Funded Status of Underfunded Pension Plans at End of Year (1) $ (30.0) $ (32.1) (1) As of December 31, 2021 and 2020, only our nonqualified plans were underfunded. These plans have no assets as they are not funded until benefits are paid. Information for pension plans with plan assets in excess of the projected benefit obligation: December 31, 2021 2020 Accumulated Benefit Obligation $ 1,804.3 $ 2,004.7 Funded Status Projected Benefit Obligation 1,822.4 2,026.3 Fair Value of Plan Assets 1,981.7 2,117.7 Funded Status of Overfunded Pension Plans at End of Year $ 159.3 $ 91.4 Our pension plans were overfunded, in aggregate, by $129.3 million at December 31, 2021 compared to being overfunded by $59.3 million at December 31, 2020. The improvement in the funded status was due primarily to favorable asset returns. We contributed $4.0 million and $2.9 million to our pension plans in 2021 and 2020, respectively. Our other postretirement benefit plans were underfunded by $262.5 million at December 31, 2021 compared to being underfunded by $304.4 million at December 31, 2020. The improvement in funded status was primarily due to employer contributions and increased discount rates. We contributed $19.8 million and $21.6 million to our other postretirement benefit plans in 2021 and 2020, respectively. In 2021 and 2020, some of our qualified pension plans paid lump sum payouts in excess of the respective plan's service cost plus interest cost, thereby meeting the requirement for settlement accounting. We recorded settlement charges of $11.4 million and $10.5 million in 2021 and 2020, respectively. Net periodic pension benefit cost for 2021 was increased by $4.0 million as a result of the interim remeasurement. The following table provides the key assumptions that were used to calculate the pension and other postretirement benefits obligations for our various plans as of December 31: Pension Benefits Other Postretirement Benefits 2021 2020 2021 2020 Weighted-average assumptions to Determine Benefit Obligation Discount Rate 2.76 % 2.38 % 2.85 % 2.49 % Rate of Compensation Increases 4.00 % 4.00 % — — Interest Crediting Rates 4.00 % 4.00 % — — Health Care Trend Rates Trend for Next Year — — 6.20 % 6.69 % Ultimate Trend — — 4.50 % 4.50 % Year Ultimate Trend Reached — — 2030 2029 We expect to make contributions of approximately $2.8 million to our pension plans and approximately $21.5 million to our postretirement medical and life plans in 2022. The following table provides benefits expected to be paid in each of the next five fiscal years, and in the aggregate for the five fiscal years thereafter. The expected benefits are estimated based on the same assumptions used to measure our benefit obligation at the end of the year and include benefits attributable to the estimated future service of employees: (in millions) Pension Benefits Other Federal Year(s) 2022 $ 157.3 $ 38.1 $ 0.4 2023 150.4 37.4 0.4 2024 145.6 36.9 0.3 2025 143.1 36.5 0.3 2026 135.7 35.8 0.3 2027-2031 598.9 168.7 1.1 The following table provides the components of the plans’ actuarially determined net periodic benefits cost for each of the three years ended December 31, 2021, 2020 and 2019: Pension Benefits Other Postretirement (in millions) 2021 2020 2019 2021 2020 2019 Components of Net Periodic Benefit (Income) Cost (1) Service cost $ 30.2 $ 32.0 $ 29.2 $ 6.2 $ 6.6 $ 5.1 Interest cost 31.4 51.6 72.3 9.9 15.4 19.2 Expected return on assets (101.6) (111.6) (108.8) (15.3) (14.4) (13.1) Amortization of prior service cost (credit) 0.1 0.7 0.2 (2.2) (2.1) (3.2) Recognized actuarial loss 21.7 33.8 45.2 4.6 4.9 2.0 Settlement/curtailment loss 11.4 10.5 9.5 — 1.5 — Total Net Periodic Benefits (Income) Cost $ (6.8) $ 17.0 $ 47.6 $ 3.2 $ 11.9 $ 10.0 (1) Service cost is presented in "Operation and maintenance" on the Statements of Consolidated Income (Loss). Non-service cost components are presented within "Other, net." The following table provides the key assumptions that were used to calculate the net periodic benefits cost for our various plans: Pension Benefits Other Postretirement 2021 2020 2019 2021 2020 2019 Weighted-average Assumptions to Determine Net Periodic Benefit Cost Discount rate - service cost 2.81 % 3.39 % 4.48 % 3.00 % 3.52 % 4.59 % Discount rate - interest cost 1.57 % 2.65 % 3.84 % 1.73 % 2.76 % 3.94 % Expected Long-Term Rate of Return on Plan Assets 5.20 % 5.70 % 6.10 % 5.50 % 5.67 % 5.83 % Rate of Compensation Increases 4.00 % 4.00 % 4.00 % — — — Interest Crediting Rates 4.00 % 4.00 % 4.00 % — — — We assumed a 5.20% and 5.50% rate of return on pension and other postretirement plan assets, respectively, for our calculation of 2021 pension benefits cost. These rates were primarily based on asset mix and historical rates of return and were adjusted in 2021 due to anticipated changes in asset allocation and projected market returns. The following table provides other changes in plan assets and projected benefit obligations recognized in other comprehensive income or regulatory asset or liability: Pension Benefits Other Postretirement (in millions) 2021 2020 2021 2020 Other Changes in Plan Assets and Projected Benefit Obligations Net prior service cost $ — $ — $ 0.1 $ — Net actuarial loss (gain) (26.0) (78.2) (23.3) 2.9 Settlements/curtailments (11.4) (10.5) — (1.5) Less: amortization of prior service cost (0.1) (0.7) 2.2 2.1 Less: amortization of net actuarial loss (21.7) (33.8) (4.6) (4.9) Less: gain attributable to spinoff to Eversource — (33.1) — — Less: prior service cost attributable to spinoff to Eversource — (2.0) — — Total Recognized in Other Comprehensive Income or Regulatory $ (59.2) $ (158.3) $ (25.6) $ (1.4) Amount Recognized in Net Periodic Benefits Cost and Other $ (66.0) $ (141.3) $ (22.4) $ 10.5

Equity

Equity	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Equity	Equity Holders of shares of our common stock are entitled to receive dividends when, as and if declared by the Board out of funds legally available. The policy of the Board has been to declare cash dividends on a quarterly basis payable on or about the 20th day of February, May, August and November. We have certain debt covenants that could potentially limit the amount of dividends we could pay in order to maintain compliance with these covenants. Refer to Note 15, "Long-Term Debt," for more information. As of December 31, 2021, these covenants did not restrict the amount of dividends that were available to be paid. Dividends paid to preferred shareholders vary based on the series of preferred stock owned. Holders of our shares of common stock are subject to the prior dividend rights of holders of our preferred stock or the depositary shares representing such preferred stock outstanding, and if full dividends have not been declared and paid on all outstanding shares of preferred stock in any dividend period, no dividend may be declared or paid or set aside for payment on our common stock. Common and preferred stock activity for 2021, 2020 and 2019 is described further below. ATM Program and Forward Sale Agreements. On November 1, 2018, we entered into five separate equity distribution agreements pursuant to which we were able to sell up to an aggregate of $500.0 million of our common stock. Four of these agreements were then amended on August 1, 2019 and one was terminated, pursuant to which we were able to sell up to an aggregate of $434.4 million of our common stock. These equity distribution agreements impacting fiscal years 2020 and 2019 expired on December 31, 2020. On February 22, 2021, we entered into six separate equity distribution agreements pursuant to which we are able to sell up to an aggregate of $750.0 million of our common stock. On February 23, 2021, under the ATM program, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. From February 24, 2021 to March 17, 2021, the forward purchaser under our forward sale agreement borrowed 6,672,740 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $22.48 per share. On December 14, 2021, the forward sale agreement was settled for $21.48 per share, resulting in $143.3 million of net proceeds. On June 1, 2021, under the ATM program, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. From June 1, 2021 to June 11, 2021, the forward purchaser under our forward sale agreement borrowed 5,852,475 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $25.63 per share. On December 13, 2021, the forward sale agreement was settled for $24.85 per share, resulting in $145.4 million of net proceeds. On August 9, 2021, under the ATM program, we executed a forward sale agreement, which allows us to issue a fixed number of shares at a price to be settled in the future. From August 9, 2021 to September 1, 2021, the forward purchaser under our forward sale agreement borrowed 5,941,598 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $25.25 per share. We may settle the forward sale agreement in shares, cash, or net shares by December 15, 2022. Had we settled all the shares under the forward sale agreement at December 31, 2021, we would have received approximately $146.8 million, based on a net price of $24.71 per share. As of December 31, 2021, the ATM program (including the impact of the forward sale agreement discussed above) had approximately $300.0 million of equity available for issuance. The program expires on December 31, 2023. The following table summarizes our activity under the ATM program. Year Ending December 31, 2021 2020 2019 Number of shares issued 12,525,215 8,459,430 8,422,498 Average price per share $ 23.95 $ 23.60 $ 27.75 Proceeds, net of fees ( in millions) $ 288.1 $ 196.5 $ 229.1 Preferred Stock. On June 11, 2018, we completed the sale of 400,000 shares of 5.650% Series A Fixed-Rate Reset Cumulative Redeemable Perpetual Preferred Stock (the "Series A Preferred Stock") at a price of $1,000 per share. The transaction resulted in $400.0 million of gross proceeds or $393.9 million of net proceeds, after deducting commissions and sale expenses. The Series A Preferred Stock was issued in a private placement pursuant to SEC Rule 144A. On December 13, 2018, we filed a registration statement with the SEC enabling holders to exchange their unregistered shares of Series A Preferred Stock for publicly registered shares with substantially identical terms. Dividends on the Series A Preferred Stock accrue and are cumulative from the date the shares of Series A Preferred Stock were originally issued to, but not including, June 15, 2023 at a rate of 5.650% per annum of the $1,000 liquidation preference per share. On and after June 15, 2023, dividends on the Series A Preferred Stock will accumulate for each five year period at a percentage of the $1,000 liquidation preference equal to the five-year U.S. Treasury Rate plus (i) in respect of each five year period commencing on or after June 15, 2023 but before June 15, 2043, a spread of 2.843% (the “Initial Margin”), and (ii) in respect of each five year period commencing on or after June 15, 2043, the Initial Margin plus 1.000%. The Series A Preferred Stock may be redeemed by us at our option on June 15, 2023, or on each date falling on the fifth anniversary thereafter, or in connection with a ratings event (as defined in the Certificate of Designation of the Series A Preferred Stock). As of December 31, 2021 and 2020, Series A Preferred Stock had $1.0 million of cumulative preferred dividends in arrears, or $2.51 per share. Holders of Series A Preferred Stock generally have no voting rights, except for limited voting rights with respect to (i) potential amendments to our certificate of incorporation that would have a material adverse effect on the existing preferences, rights, powers or duties of the Series A Preferred Stock, (ii) the creation or issuance of any security ranking on a parity with the Series A Preferred Stock if the cumulative dividends payable on then outstanding Series A Preferred Stock are in arrears, or (iii) the creation or issuance of any security ranking senior to the Series A Preferred Stock. The Series A Preferred Stock does not have a stated maturity and is not subject to mandatory redemption or any sinking fund. The Series A Preferred Stock will remain outstanding indefinitely unless repurchased or redeemed by us. Any such redemption would be effected only out of funds legally available for such purposes and will be subject to compliance with the provisions of our outstanding indebtedness. On December 5, 2018, we completed the sale of 20,000,000 depositary shares with an aggregate liquidation preference of $500,000,000 under the Company’s registration statement on Form S-3. Each depositary share represents 1/1,000th ownership interest in a share of our 6.500% Series B Fixed-Rate Reset Cumulative Redeemable Perpetual Preferred Stock, liquidation preference $25,000 per share (equivalent to $25 per depositary share) (the “Series B Preferred Stock"). The transaction resulted in $500.0 million of gross proceeds or $486.1 million of net proceeds, after deducting commissions and sale expenses. Dividends on the Series B Preferred Stock accrue and are cumulative from the date the shares of Series B Preferred Stock were originally issued to, but not including, March 15, 2024 at a rate of 6.500% per annum of the $25,000 liquidation preference per share. On and after March 15, 2024, dividends on the Series B Preferred Stock will accumulate for each five year period at a percentage of the $25,000 liquidation preference equal to the five-year U.S. Treasury Rate plus (i) in respect of each five year period commencing on or after March 15, 2024 but before March 15, 2044, a spread of 3.632% (the “Initial Margin”), and (ii) in respect of each five year period commencing on or after March 15, 2044, the Initial Margin plus 1.000%. The Series B Preferred Stock may be redeemed by us at our option on March 15, 2024, or on each date falling on the fifth anniversary thereafter, or in connection with a ratings event (as defined in the Certificate of Designation of the Series B Preferred Stock). As of December 31, 2021 and 2020, Series B Preferred Stock had $1.4 million of cumulative preferred dividends in arrears, or $72.23 per share. In addition, 20,000 shares of Series B–1 Preferred Stock, par value $0.01 per share, were outstanding as of December 31, 2021. Holders of Series B–1 Preferred Stock are not entitled to receive dividend payments and have no conversion rights. The Series B–1 Preferred Stock is paired with the Series B Preferred Stock and may not be transferred, redeemed or repurchased except in connection with the simultaneous transfer, redemption or repurchase of the underlying Series B Preferred Stock. Holders of Series B Preferred Stock generally have no voting rights, except for limited voting rights with respect to (i) potential amendments to our certificate of incorporation that would have a material adverse effect on the existing preferences, rights, powers or duties of the Series B Preferred Stock, (ii) the creation or issuance of any security ranking on a parity with the Series B Preferred Stock if the cumulative dividends payable on then outstanding Series B Preferred Stock are in arrears, or (iii) the creation or issuance of any security ranking senior to the Series B Preferred Stock. In addition, if and whenever dividends on any shares of Series B Preferred Stock shall not have been declared and paid for at least six dividend periods, whether or not consecutive, the number of directors then constituting our Board of Directors shall automatically be increased by two until all accumulated and unpaid dividends on the Series B Preferred Stock shall have been paid in full, and the holders of Series B-1 Preferred Stock, voting as a class together with the holders of any outstanding securities ranking on a parity with the Series B-1 Preferred Stock and having like voting rights that are exercisable at the time and entitled to vote thereon, shall be entitled to elect the two additional directors. The Series B Preferred Stock does not have a stated maturity and is not subject to mandatory redemption or any sinking fund. The Series B Preferred Stock will remain outstanding indefinitely unless repurchased or redeemed by us. Any such redemption would be effected only out of funds legally available for such purposes and will be subject to compliance with the provisions of our outstanding indebtedness. The following table summarizes preferred stock by outstanding series of shares: Year ended December 31, December 31, December 31, 2021 2020 2019 2021 2020 (in millions except shares and per share amounts) Liquidation Preference Per Share Shares Dividends Declared Per Share Outstanding 5.650% Series A $ 1,000.00 400,000 $ 56.50 $ 56.50 $ 56.50 $ 393.9 $ 393.9 6.500% Series B $ 25,000.00 20,000 $ 1,625.00 $ 1,625.00 $ 1,674.65 $ 486.1 $ 486.1 Series C (1) $ 1,000.00 862,500 — — — $ 666.5 $ — (1) The Series C Mandatory Convertible Preferred Stock initially will not bear any dividends. We recorded the initial present value of the purchase contract payments as a liability with a corresponding reduction to preferred stock. Equity Units. On April 19, 2021, we completed the sale of 8.625 million Equity Units, initially consisting of Corporate Units, each with a stated amount of $100. The offering generated net proceeds of $835.5 million, after underwriting and issuance expenses. Each Corporate Unit consists of a forward contract to purchase shares of our common stock in the future and a 1/10th, or 10%, undivided beneficial ownership interest in one share of Series C Mandatory Convertible Preferred Stock, par value $0.01 per share, with a liquidation preference of $1,000 per share. The purchase contract obligates holders to purchase shares of our common stock on December 1, 2023, subject to early settlement in certain situations. The purchase price paid under the purchase contract is $100 and the number of shares to be purchased will be determined under a settlement rate formula based on the volume-weighted average share price of our common stock near the settlement date, subject to a maximum settlement rate. The Series C Mandatory Convertible Preferred Stock will initially be pledged upon issuance as collateral to secure the purchase of common stock under the related purchase contracts. We will pay quarterly contract adjustment payments at the rate of 7.75% per year on the stated amount of $100 per Equity Unit. The contract adjustment payments are payable in cash, shares of our common stock or a combination thereof, at our election. We have the right to defer the payment of contract adjustment payments until no later than the purchase contract settlement date. If we exercise our option to defer the payment of contract adjustment payments, then until the deferred contract adjustment payments have been paid, we will not declare or pay any dividends on, or make any distributions on, or redeem, purchase or acquire, or make a liquidation payment with respect to, any shares of our capital stock; make any payment of principal of, or interest or premium, if any, on, or repay, repurchase or redeem any of our debt securities that rank on parity with, or junior to, the contract adjustment payments; or make any guarantee payments under any guarantee by us of securities of any of our subsidiaries if our guarantee ranks on parity with, or junior to, the contract adjustment payments. The Series C Mandatory Convertible Preferred Stock initially will not bear any dividends and the liquidation preference of the mandatory convertible preferred stock will not accrete. The Series C Mandatory Convertible Preferred Stock is expected to be remarketed prior to December 1, 2023. Following a successful remarketing, dividends may become payable on the Series C Mandatory Convertible Preferred Stock and/or the minimum conversion rate of the Series C Mandatory Convertible Preferred Stock may be increased. Each share of Series C Mandatory Convertible Preferred Stock, unless previously converted, will automatically convert based on a conversion rate on the mandatory conversion date, which is expected to be on or about March 1, 2024. The conversion rate will be determined based on the volume-weighted average share price of our common stock near the conversion date, subject to a minimum and maximum conversion rate. If no successful remarketing of the Series C Mandatory Convertible Preferred Stock has previously occurred, effective as of December 1, 2023, the conversion rate will be zero, no shares of our common stock will be delivered upon automatic conversion and each share of Series C Mandatory Convertible Preferred Stock will be automatically transferred to us on the mandatory conversion date without any payment of cash or shares of our common stock thereon. In the event of such a remarketing failure, any shares of Series C Mandatory Convertible Preferred Stock held as part of Corporate Units will be automatically delivered to us on December 1, 2023 in full satisfaction of the relevant holder's obligation under the related purchase contracts. The Series C Mandatory Convertible Preferred Stock and forward purchase contracts are legally detachable and separately exercisable, however, due to the economic linkage between the forward purchase contract and the Series C Mandatory Convertible Preferred Stock, we have concluded that the ability to separate the Corporate Units is non-substantive. Accordingly, we are accounting for the Corporate Units as a single unit of account. We recorded the initial present value of the purchase contract payments as a liability with a corresponding reduction to preferred stock. The current portion of this liability is included in "Other accruals," and the noncurrent portion is included in "Other noncurrent liabilities" on the Consolidated Balance Sheets. Purchase contract payments are recorded against this liability. Accretion of the stock purchase contract liability is recorded as interest expense. Refer to Note 5, "Earnings Per Share," for additional information regarding our application of diluted EPS to the shares underlying purchase contracts and the Series C Mandatory Convertible Preferred Stock as part of the Equity Units. Under the terms of the Equity Units, assuming no anti-dilution or other adjustments such as a fundamental change, the maximum number of shares of common stock we will issue under the purchase contracts is 35.2 million and maximum number of shares of common stock we will issue under the Series C Mandatory Convertible Preferred Stock is 35.2 million. Selected information about the Equity Units is presented below: (in millions except contract rate) Issuance Date Units Issued Total Net Proceeds (1) Purchase Contract Annual Rate Purchase Contract Liability (2) Equity Units April 19, 2021 8.625 $ 835.5 7.75 % $ 168.8 (1) Issuance costs of $27.0 million were recorded on a relative fair value basis as a reduction to preferred stock of $22.5 million and a reduction to the purchase contract liability of $4.5 million. (2) Cash payments of $41.2 million and zero were made during the years ended December 31, 2021 and December 31, 2020, respectively. The purchase contract liability was $129.4 million at December 31, 2021. Noncontrolling Interest in Consolidated Subsidiaries. As of December 31, 2021 and 2020, NIPSCO and tax equity partners have completed their cash contributions into the Indiana Crossroads Wind and Rosewater joint ventures. Earnings, tax attributes and cash flows are allocated to both NIPSCO and the respective tax equity partners in varying percentages by category and over the life of the partnership. The tax equity partner's contributions, net of these allocations, is represented as a noncontrolling interest within total equity on the Consolidated Balance Sheets. Refer to Note 4, "Variable Interest Entities," for more information.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement, Noncash Expense [Abstract]
Share-Based Compensation	Share-Based Compensation Prior to May 19, 2020 we issued share-based compensation to employees and non-employee directors under the NiSource Inc. 2010 Omnibus Plan ("2010 Omnibus Plan"), which was most recently approved by stockholders at the Annual Meeting of Stockholders held on May 12, 2015. The 2010 Omnibus Plan provided for awards to employees and non-employee directors of incentive and nonqualified stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares, performance units, cash-based awards and other stock-based awards and superseded the Director Stock Incentive Plan (“Director Plan”) with respect to grants made after the effective date of the 2010 Omnibus Plan. The stockholders approved and adopted the NiSource Inc. 2020 Omnibus Incentive Plan ("2020 Omnibus Plan") at the Annual Meeting of Stockholders held on May 19, 2020. The 2020 Omnibus Plan provides for awards to employees and non-employee directors of incentive and nonqualified stock options, stock appreciation rights, restricted stock, restricted stock units, performance shares, performance units, cash-based awards and other stock-based awards and supersedes the 2010 Omnibus Plan with respect to grants made after the effective date of the 2020 Omnibus Plan. The 2020 Omnibus Plan provides that the number of shares of common stock of NiSource available for awards is 10,000,000 plus the number of shares subject to outstanding awards that expire or terminate for any reason that were granted under the 2020 Omnibus Plan, the 2010 Omnibus Plan or any other equity plan under which awards were outstanding as of May 19, 2020. At December 31, 2021, there were 9,081,947 shares available for future awards under the 2020 Omnibus Plan. We recognized stock-based employee compensation expense of $16.7 million, $13.5 million and $16.3 million, during 2021, 2020 and 2019, respectively, as well as related tax benefits of $4.0 million, $3.3 million and $4.0 million, respectively. We recognized related excess tax expense from the distribution of vested share-based employee compensation of $0.4 million in 2020, and excess tax benefits of $0.4 million and $0.8 million in 2021 and 2019, respectively. As of December 31, 2021, the total remaining unrecognized compensation cost related to non-vested awards amounted to $25.1 million, which will be amortized over the weighted-average remaining requisite service period of 1.8 years. Restricted Stock Units and Restricted Stock . We granted 285,755, 235,100, and 166,031 restricted stock units and shares of restricted stock to employees, subject to service conditions in 2021, 2020, and 2019, respectively. The total grant date fair value of the restricted stock units and shares of restricted stock during 2021, 2020, and 2019, respectively, was $5.7 million, $6.1 million, and $4.1 million based on the average market price of our common stock at the date of each grant less the present value of any dividends not received during the vesting period, which will be expensed over the vesting period which is generally three years. As of December 31, 2021, 274,796, 198,303, and 99,055 non-vested restricted stock units and shares of restricted stock granted in 2021, 2020, and 2019, respectively, were outstanding. If an employee terminates employment before the service conditions lapse under the 2019, 2020 or 2021 awards due to (1) retirement or disability (as defined in the award agreement), or (2) death, the service conditions will lapse on the date of such termination with respect to a pro rata portion of the restricted stock units and shares of restricted stock based upon the percentage of the service period satisfied between the grant date and the date of the termination of employment. In the event of a change in control (as defined in the award agreement), all unvested shares of restricted stock and restricted stock units awarded will immediately vest upon termination of employment occurring in connection with a change in control. Termination due to any other reason will result in all unvested shares of restricted stock and restricted stock units awarded being forfeited effective on the employee’s date of termination. A summary of our restricted stock unit award transactions for the year ended December 31, 2021 is as follows: (shares) Restricted Stock Weighted Average Non-vested at December 31, 2020 478,227 24.51 Granted 285,755 19.83 Forfeited (36,697) 23.72 Vested (155,131) 22.66 Non-vested at December 31, 2021 572,154 22.72 Employee Performance Shares . We granted 973,885 performance shares subject to service, performance and/or market-based vesting conditions in 2021. In regards to 390,941 performance shares granted, the performance conditions are based on the achievement of relative total shareholder return. The number of shares that are eligible to vest based on the Company's relative total shareholder return performance will be adjusted based on a performance magnifier related to safety. In regards to remaining 582,944 performance shares granted, the performance conditions are based on the achievement of one non-GAAP financial measure and/or achievement of relative total shareholder return. The number of shares that are eligible to vest based on these performance conditions will be adjusted based on performance of the magnifier framework for 2021 awards, outlined below. The financial measure is cumulative net operating earnings per share ("NOEPS"), which we define as income from continuing operations adjusted for certain items. Relative total shareholder return, a market-based vesting condition, which we define as the annualized growth in dividends and share price of a share of our common stock (calculated using a 20 trading day average of our closing price over the performance period, approximately) compared to the total shareholder return of a predetermined peer group of companies. A relative shareholder return result within the first quartile will result in an increase to the NOEPS shares of 25%, while a relative shareholder return result within the fourth quartile will result in a decrease of 25%. A Monte Carlo analysis was used to value the portion of these awards dependent on the market-based vesting condition. The grant date fair value of the NOEPS shares is based on the closing stock price of our common stock at the date of each grant, which will be expensed over the requisite service period of three years. See table below for further details on these awards. For the 2021 awards, the magnifier framework consists of three areas of focus including safety, environment, and diversity, equity and inclusion ("DE&I"), representing 20%, 10% and 10%, respectively. We granted 528,729 and 552,389 performance shares subject to service, performance and market-based vesting conditions in 2020 and 2019, respectively. The performance conditions are based on the achievement of one non-GAAP financial measure, relative total shareholder return and additional operational measures as outlined below. The financial measure is cumulative net operating earnings per share ("NOEPS"), which we define as income from continuing operations adjusted for certain items. The number of cumulative NOEPS shares determined using this measure shall be increased or decreased based on our relative total shareholder return, a market-based vesting condition, which we define as the annualized growth in dividends and share price of a share of our common stock (calculated using a 20 trading day average of our closing price over the performance period, approximately) compared to the total shareholder return of a predetermined peer group of companies. A relative shareholder return result within the first quartile will result in an increase to the NOEPS shares of 25%, while a relative shareholder return result within the fourth quartile will result in a decrease of 25%. A Monte Carlo analysis was used to value the portion of these awards dependent on the market-based vesting condition. The grant date fair value of the NOEPS shares is based on the average market price of our common stock at the date of each grant less the present value of dividends not received during the vesting period, which will be expensed over the requisite service period of three years. See table below for further details on these awards. If a threshold level of cumulative NOEPS financial performance is achieved, additional operational measures, which we refer to as the customer value framework and which consists of equally weighted areas of focus, apply. Each area of focus represents an equal portion of the customer value framework shares, and the targets for all areas of focus must be met for the customer value framework shares to vest at 100%. The grant date fair value of the customer value framework shares is based on the average market price of our common stock on the grant date of each award less the present value of dividends not received during the vesting period, which will be expensed over the requisite service period of three years for those customer value framework shares that are granted. See table below for further details on these awards. For the 2020 awards, the customer value framework consists of four equally weighted areas of focus including safety, customer satisfaction, culture and environmental, each representing 25% of the customer value framework shares. For the 2019 awards, the customer value framework consists of five equally weighted areas of focus including financial and all those noted for the 2020 awards, each representing 20% of the customer value framework shares. The following table presents details of the performance awards described above. Award Year Service Conditions Lapse date Performance Period Award Conditions Shares outstanding at 12/31/2021 (shares) Grant Date Fair Value (in millions) 2021 02/28/24 01/01/2021- Non-GAAP Financial Measure 278,328 $ 6.5 Relative Total Shareholder Return 278,328 $ 6.7 Relative Total Shareholder Return 124,200 $ 3.2 02/28/23 01/01/2021- 12/31/2022 Relative Total Shareholder Return 252,082 $ 4.8 2020 02/28/23 01/01/2020- Non-GAAP Financial Measure 349,686 $ 11.7 Operational Measures 80,696 $ 2.6 2019 02/28/22 01/01/2019- Non-GAAP Financial Measure 353,302 $ 11.7 Operational Measures 81,528 $ 2.5 A summary of our performance award transactions for the year ended December 31, 2021 is as follows: (shares) Performance Weighted Average Non-vested at December 31, 2020 1,384,336 25.09 Granted 973,885 21.76 Forfeited (133,695) 25.25 Vested (426,375) 22.09 Non-vested at December 31, 2021 1,798,151 23.78 Non-employee Director Awards . As of May 19, 2020, awards to non-employee directors may be made only under the 2020 Omnibus Plan. Currently, restricted stock units are granted annually to non-employee directors, subject to a non-employee director’s election to defer receipt of such restricted stock unit award. The non-employee director’s annual award of restricted stock units vest on the first anniversary of the grant date subject to special pro-rata vesting rules in the event of retirement or disability (as defined in the award agreement), or death. The vested restricted stock units are payable as soon as practicable following vesting except as otherwise provided pursuant to the non-employee director’s deferral election. Certain restricted stock units remain outstanding from the 2010 Omnibus Plan and the Director Plan. All such awards are fully vested and shall be distributed to the directors upon their separation from the Board. As of December 31, 2021, 252,673 restricted stock units are outstanding to non-employee directors under either the 2020 Omnibus Plan, the 2010 Omnibus Plan or the Director Plan. Of this amount, 66,273 restricted stock units are unvested and expected to vest.

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2021
Long-term Debt, Current and Noncurrent [Abstract]
Long-Term Debt	Long-Term Debt Our long-term debt as of December 31, 2021 and 2020 is as follows: Long-term debt type Maturity as of December 31, 2021 Weighted average interest rate (%) Outstanding balance as of December 31, (in millions) 2021 2020 Senior notes: NiSource August 2025 0.95 % 1,250.0 1,250.0 NiSource May 2027 3.49 % 1,000.0 1,000.0 NiSource December 2027 6.78 % 3.0 3.0 NiSource September 2029 2.95 % 750.0 750.0 NiSource May 2030 3.60 % 1,000.0 1,000.0 NiSource February 2031 1.70 % 750.0 750.0 NiSource December 2040 6.25 % 152.6 152.6 NiSource June 2041 5.95 % 347.4 347.4 NiSource February 2042 5.80 % 250.0 250.0 NiSource February 2043 5.25 % 500.0 500.0 NiSource February 2044 4.80 % 750.0 750.0 NiSource February 2045 5.65 % 500.0 500.0 NiSource May 2047 4.38 % 1,000.0 1,000.0 NiSource March 2048 3.95 % 750.0 750.0 Total senior notes $ 9,003.0 $ 9,003.0 Medium term notes: NiSource April 2022 to May 2027 7.99 % $ 49.0 $ 49.0 NIPSCO August 2022 to August 2027 7.61 % 68.0 68.0 Columbia of Massachusetts December 2025 to February 2028 6.37 % 15.0 15.0 Total medium term notes $ 132.0 $ 132.0 Finance leases: NiSource Corporate Services March 2022 to December 2025 1.73 % 51.4 49.4 NIPSCO December 2027 to January 2033 1.86 % 18.7 16.0 Columbia of Ohio December 2025 to March 2044 6.15 % 87.8 91.2 Columbia of Virginia July 2029 to November 2039 6.28 % 17.7 18.4 Columbia of Kentucky May 2027 3.79 % 0.2 0.3 Columbia of Pennsylvania August 2027 to May 2035 6.35 % 9.8 19.7 Total finance leases 185.6 195.0 Unamortized issuance costs and discounts $ (79.1) $ (86.9) Total Long-Term Debt $ 9,241.5 $ 9,243.1 There was no long-term debt activity during 2021. Details of our 2020 long-term debt related activity are summarized below: • On April 13, 2020, we completed the issuance and sale of $1.0 billion of 3.60% senior unsecured notes maturing in 2030, which resulted in approximately $987.8 million of net proceeds after deducting commissions and expenses. • On August 18, 2020, we completed the issuance and sale of $1.25 billion of 0.95% senior unsecured notes maturing in 2025 and $750.0 million of 1.70% senior unsecured notes maturing in 2031, which resulted in approximately $1,980.4 million of net proceeds after deducting commissions and expenses. • In August 2020, we executed tender offers for $969.3 million of outstanding notes consisting of a combination of our 4.45% notes due 2021, 2.65% notes due 2022, 3.85% notes due 2023, 3.65% notes due 2023, 6.25% notes due 2040, and 5.95% notes due 2041. In August and September 2020, we redeemed $609.3 million of outstanding notes representing the remainder of our 4.45% notes due 2021, 2.65% notes due 2022, 3.85% notes due 2023, and 3.65% notes due 2023 and all of our 5.89% notes due 2025. In conjunction with the debt retired, we recorded a $231.8 million loss on early extinguishment of long-term debt, primarily attributable to early redemption premiums. • In September 2020, Columbia of Massachusetts redeemed $25.0 million of its outstanding 6.26% notes due 2028. In conjunction with the debt retired, Columbia of Massachusetts recorded an $11.7 million loss on early extinguishment of long-term debt, primarily attributable to early redemption premiums. Under the terms of the Asset Purchase Agreement, Columbia of Massachusetts’ net working capital at the closing of the sale of the Massachusetts Business was increased by 50% of the debt extinguishment costs, which was approximately $5.3 million. See Note 19-A, "Contractual Obligations," for the outstanding long-term debt maturities at December 31, 2021. Unamortized debt expense, premium and discount on long-term debt applicable to outstanding bonds are being amortized over the life of such bonds. We are subject to a financial covenant under our revolving credit facility which requires us to maintain a debt to capitalization ratio that does not exceed 70%. As of December 31, 2021, the ratio was 57.4%. We are also subject to certain other non-financial covenants under the revolving credit facility. Such covenants include a limitation on the creation or existence of new liens on our assets, generally exempting liens on utility assets, purchase money security interests, preexisting security interests and an additional subset of assets equal to $200 million. An asset sale covenant generally restricts the sale, conveyance, lease, transfer or other disposition of our assets to those dispositions that are for a price not materially less than fair market of such assets, that would not materially impair our ability to perform obligations under the revolving credit facility, and that together with all other such dispositions, would not have a material adverse effect. The covenant also restricts dispositions to no more than 15% of our consolidated total assets on December 31, 2020. The revolving credit facility also includes a cross-default provision, which triggers an event of default under the credit facility in the event of an uncured payment default relating to any indebtedness of us or any of our subsidiaries in a principal amount of $75.0 million or more. Our indentures generally do not contain any financial maintenance covenants. However, our indentures are generally subject to cross-default provisions ranging from uncured payment defaults of $5 million to $50 million, and limitations on the incurrence of liens on our assets, generally exempting liens on utility assets, purchase money security interests, preexisting security interests and an additional subset of assets capped at 10% of our consolidated net tangible assets.

Short-Term Borrowings

Short-Term Borrowings	12 Months Ended
	Dec. 31, 2021
Short-term Debt [Abstract]
Short-Term Borrowings	Short-Term Borrowings We generate short-term borrowings from our revolving credit facility, commercial paper program, and accounts receivable transfer programs. Each of these borrowing sources is described further below. Revolving Credit Facility. We maintain a revolving credit facility to fund ongoing working capital requirements, including the provision of liquidity support for our commercial paper program, provide for issuance of letters of credit and also for general corporate purposes. Our revolving credit facility has a program limit of $1.85 billion and is comprised of a syndicate of banks led by Barclays. On February 18, 2022, we extended the termination date of our revolving credit facility to February 18, 2027. At December 31, 2021 and 2020, we had no outstanding borrowings under this facility. Commercial Paper Program. Our commercial paper program has a program limit of up to $1.5 billion with a dealer group comprised of Barclays, Citigroup, Credit Suisse and Wells Fargo. We had $560.0 million and $503.0 million of commercial paper outstanding with weighted-average interest rates of 0.24% and 0.27% as of December 31, 2021 and 2020, respectively. Accounts Receivable Transfer Programs. Columbia of Ohio, NIPSCO and Columbia of Pennsylvania each maintain a receivables agreement whereby they transfer their customer accounts receivables to third party financial institutions through wholly-owned and consolidated special purpose entities. The three agreements expire between May 2022 and October 2022 and may be further extended if mutually agreed to by the parties thereto. All receivables transferred to third parties are valued at face value, which approximates fair value due to their short-term nature. The amount of the undivided percentage ownership interest in the accounts receivables transferred is determined in part by required loss reserves under the agreements. Transfers of accounts receivable are accounted for as secured borrowings resulting in the recognition of short-term borrowings on the Consolidated Balance Sheets. As of December 31, 2021, the maximum amount of debt that could be recognized related to our accounts receivable programs is $270.0 million. We had no short-term borrowings related to the securitization transactions as of December 31, 2021 and December 31, 2020. For the years ended December 31, 2021 and 2020, zero and $353.2 million, respectively, were recorded as cash flows used for financing activities related to the change in short-term borrowings due to securitization transactions. For the accounts receivable transfer programs, we pay used facility fees for amounts borrowed, unused commitment fees for amounts not borrowed, and upfront renewal fees. Fees associated with the securitization transactions were $1.4 million, $2.6 million, and $2.6 million for the years ended December 31, 2021, 2020 and 2019, respectively. Columbia of Ohio, NIPSCO and Columbia of Pennsylvania remain responsible for collecting on the receivables securitized, and the receivables cannot be transferred to another party. Items listed above are presented net in the Statements of Consolidated Cash Flows as their maturities are less than 90 days.

Leases

Leases	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Lessee, Operating Leases	Leases Lease Descriptions. We are the lessee for substantially all of our leasing activity, which includes operating and finance leases for corporate and field offices, railcars, fleet vehicles and certain IT assets. Our corporate and field office leases have remaining lease terms between 1 and 22 years with options to renew the leases for up to 25 years. We lease railcars to transport coal to and from our electric generation facilities in Indiana. Our railcars are specifically identified in the lease agreement, which have a remaining lease term of 1 year with options to renew for 1 year. Our fleet vehicles include trucks, trailers and equipment that have been customized specifically for use in the utility industry. We lease fleet vehicles on 1 year terms, after which we have the option to extend on a month-to-month basis or terminate with written notice. ROU assets and liabilities on our Consolidated Balance Sheets do not include obligations for possible fleet vehicle lease renewals beyond the initial lease term. While we have the ability to renew these leases beyond the initial term, we are not reasonably certain to do so. We lease the majority of our IT assets under 4 year lease terms. Ownership of leased IT assets is transferred to us at the end of the lease term. We have not provided material residual value guarantees for our leases, nor do our leases contain material restrictions or covenants. Lease contracts containing renewal and termination options are mostly exercisable at our sole discretion. Certain of our real estate and railcar leases include renewal periods in the measurement of the lease obligation if we have deemed the renewals reasonably certain to be exercised. With respect to service contracts involving the use of assets, if we have the right to direct the use of the asset and obtain substantially all economic benefits from the use of an asset, we account for the service contract as a lease. Unless specifically provided to us by the lessor, we utilize NiSource's collateralized incremental borrowing rate commensurate to the lease term as the discount rate for all of our leases. ASC 842 permits a lessee, by class of underlying asset, not to separate nonlease components from lease components. Our policy is to apply this expedient for our leases of fleet vehicles, IT assets and railcars when calculating their respective lease liabilities. Lease costs for the years ended December 31, 2021 and December 31, 2020 are presented in the table below. These costs include both amounts recognized in expense and amounts capitalized as part of the cost of another asset. Income statement presentation for these costs (when ultimately recognized on the income statement) is also included: Year Ended December 31, (in millions) Income Statement Classification 2021 2020 Finance lease cost Amortization of right-of-use assets Depreciation and amortization $ 28.8 $ 23.4 Interest on lease liabilities Interest expense, net 9.4 11.1 Total finance lease cost 38.2 34.5 Operating lease cost Operation and maintenance 15.6 20.3 Total lease cost $ 53.8 $ 54.8 Our right-of-use assets and liabilities are presented in the following lines on the Consolidated Balance Sheets: At December 31, (in millions) Balance Sheet Classification 2021 2020 Assets Finance leases Net Property, Plant and Equipment $ 165.7 $ 176.8 Operating leases Deferred charges and other 33.8 39.9 Total leased assets 199.5 216.7 Liabilities Current Finance leases Current portion of long-term debt 28.1 23.3 Operating leases Other accruals 6.7 10.3 Noncurrent Finance leases Long-term debt, excluding amounts due within one year 157.5 171.7 Operating leases Other noncurrent liabilities 27.9 29.9 Total lease liabilities $ 220.2 $ 235.2 Other pertinent information related to leases was as follows: Year Ended December 31, (in millions) 2021 2020 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows used for finance leases $ 9.4 $ 11.1 Operating cash flows used for operating leases 15.4 20.2 Financing cash flows used for finance leases 25.7 18.4 Right-of-use assets obtained in exchange for lease obligations Finance leases 22.4 59.3 Operating leases $ 6.0 $ 10.9 December 31, 2021 December 31, 2020 Weighted-average remaining lease term (years) Finance leases 10.6 11.2 Operating leases 8.5 8.0 Weighted-average discount rate Finance leases 5.0 % 5.1 % Operating leases 3.7 % 4.0 % Maturities of our lease liabilities as of December 31, 2021 were as follows: As of December 31, 2021, (in millions) Total Finance Leases Operating Leases 2022 $ 45.1 $ 37.2 $ 7.9 2023 38.5 33.6 4.9 2024 30.2 25.6 4.6 2025 23.2 19.2 4.0 2026 19.6 15.8 3.8 Thereafter 129.1 112.9 16.2 Total lease payments 285.7 244.3 41.4 Less: Imputed interest (65.5) (58.7) (6.8) Total 220.2 185.6 34.6 Reported as of December 31, 2021 Short-term lease liabilities 34.8 28.1 6.7 Long-term lease liabilities 185.4 157.5 27.9 Total lease liabilities $ 220.2 $ 185.6 $ 34.6 There were no leases signed but not yet commenced as of December 31, 2021.
Lessee, Finance Leases	Leases Lease Descriptions. We are the lessee for substantially all of our leasing activity, which includes operating and finance leases for corporate and field offices, railcars, fleet vehicles and certain IT assets. Our corporate and field office leases have remaining lease terms between 1 and 22 years with options to renew the leases for up to 25 years. We lease railcars to transport coal to and from our electric generation facilities in Indiana. Our railcars are specifically identified in the lease agreement, which have a remaining lease term of 1 year with options to renew for 1 year. Our fleet vehicles include trucks, trailers and equipment that have been customized specifically for use in the utility industry. We lease fleet vehicles on 1 year terms, after which we have the option to extend on a month-to-month basis or terminate with written notice. ROU assets and liabilities on our Consolidated Balance Sheets do not include obligations for possible fleet vehicle lease renewals beyond the initial lease term. While we have the ability to renew these leases beyond the initial term, we are not reasonably certain to do so. We lease the majority of our IT assets under 4 year lease terms. Ownership of leased IT assets is transferred to us at the end of the lease term. We have not provided material residual value guarantees for our leases, nor do our leases contain material restrictions or covenants. Lease contracts containing renewal and termination options are mostly exercisable at our sole discretion. Certain of our real estate and railcar leases include renewal periods in the measurement of the lease obligation if we have deemed the renewals reasonably certain to be exercised. With respect to service contracts involving the use of assets, if we have the right to direct the use of the asset and obtain substantially all economic benefits from the use of an asset, we account for the service contract as a lease. Unless specifically provided to us by the lessor, we utilize NiSource's collateralized incremental borrowing rate commensurate to the lease term as the discount rate for all of our leases. ASC 842 permits a lessee, by class of underlying asset, not to separate nonlease components from lease components. Our policy is to apply this expedient for our leases of fleet vehicles, IT assets and railcars when calculating their respective lease liabilities. Lease costs for the years ended December 31, 2021 and December 31, 2020 are presented in the table below. These costs include both amounts recognized in expense and amounts capitalized as part of the cost of another asset. Income statement presentation for these costs (when ultimately recognized on the income statement) is also included: Year Ended December 31, (in millions) Income Statement Classification 2021 2020 Finance lease cost Amortization of right-of-use assets Depreciation and amortization $ 28.8 $ 23.4 Interest on lease liabilities Interest expense, net 9.4 11.1 Total finance lease cost 38.2 34.5 Operating lease cost Operation and maintenance 15.6 20.3 Total lease cost $ 53.8 $ 54.8 Our right-of-use assets and liabilities are presented in the following lines on the Consolidated Balance Sheets: At December 31, (in millions) Balance Sheet Classification 2021 2020 Assets Finance leases Net Property, Plant and Equipment $ 165.7 $ 176.8 Operating leases Deferred charges and other 33.8 39.9 Total leased assets 199.5 216.7 Liabilities Current Finance leases Current portion of long-term debt 28.1 23.3 Operating leases Other accruals 6.7 10.3 Noncurrent Finance leases Long-term debt, excluding amounts due within one year 157.5 171.7 Operating leases Other noncurrent liabilities 27.9 29.9 Total lease liabilities $ 220.2 $ 235.2 Other pertinent information related to leases was as follows: Year Ended December 31, (in millions) 2021 2020 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows used for finance leases $ 9.4 $ 11.1 Operating cash flows used for operating leases 15.4 20.2 Financing cash flows used for finance leases 25.7 18.4 Right-of-use assets obtained in exchange for lease obligations Finance leases 22.4 59.3 Operating leases $ 6.0 $ 10.9 December 31, 2021 December 31, 2020 Weighted-average remaining lease term (years) Finance leases 10.6 11.2 Operating leases 8.5 8.0 Weighted-average discount rate Finance leases 5.0 % 5.1 % Operating leases 3.7 % 4.0 % Maturities of our lease liabilities as of December 31, 2021 were as follows: As of December 31, 2021, (in millions) Total Finance Leases Operating Leases 2022 $ 45.1 $ 37.2 $ 7.9 2023 38.5 33.6 4.9 2024 30.2 25.6 4.6 2025 23.2 19.2 4.0 2026 19.6 15.8 3.8 Thereafter 129.1 112.9 16.2 Total lease payments 285.7 244.3 41.4 Less: Imputed interest (65.5) (58.7) (6.8) Total 220.2 185.6 34.6 Reported as of December 31, 2021 Short-term lease liabilities 34.8 28.1 6.7 Long-term lease liabilities 185.4 157.5 27.9 Total lease liabilities $ 220.2 $ 185.6 $ 34.6 There were no leases signed but not yet commenced as of December 31, 2021.

Fair Value

Fair Value	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value	Fair Value A. Fair Value Measurements Recurring Fair Value Measurements The following tables present financial assets and liabilities measured and recorded at fair value on our Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2021 and December 31, 2020: Recurring Fair Value Measurements December 31, 2021 ( in millions ) Quoted Prices Significant Other Significant Balance as of December 31, 2021 Assets Risk management assets $ — $ 24.4 $ — $ 24.4 Available-for-sale debt securities — 171.8 — 171.8 Total $ — $ 196.2 $ — $ 196.2 Liabilities Risk management liabilities $ — $ 144.2 $ — $ 144.2 Total $ — $ 144.2 $ — $ 144.2 Recurring Fair Value Measurements December 31, 2020 ( in millions ) Quoted Prices Significant Other Significant Balance as of December 31, 2020 Assets Risk management assets $ — $ 13.2 $ — $ 13.2 Available-for-sale debt securities — 170.9 — 170.9 Total $ — $ 184.1 $ — $ 184.1 Liabilities Risk management liabilities $ — $ 222.8 $ — $ 222.8 Total $ — $ 222.8 $ — $ 222.8 Risk Management Assets and Liabilities. Risk management assets and liabilities include interest rate swaps, exchange-traded NYMEX futures and NYMEX options and non-exchange-based forward purchase contracts. Level 1- When utilized, exchange-traded derivative contracts are based on unadjusted quoted prices in active markets and are classified within Level 1. These financial assets and liabilities are secured with cash on deposit with the exchange; therefore, nonperformance risk has not been incorporated into these valuations. These financial assets and liabilities are deemed to be cleared and settled daily by NYMEX as the related cash collateral is posted with the exchange. As a result of this exchange rule, NYMEX derivatives are considered to have no fair value at the balance sheet date for financial reporting purposes, and are presented in Level 1 net of posted cash; however, the derivatives remain outstanding and are subject to future commodity price fluctuations until they are settled in accordance with their contractual terms. Level 2- Certain non-exchange-traded derivatives are valued using broker or over-the-counter, on-line exchanges. In such cases, these non-exchange-traded derivatives are classified within Level 2. Non-exchange-based derivative instruments include swaps, forwards, and options. In certain instances, these instruments may utilize models to measure fair value. We use a similar model to value similar instruments. Valuation models utilize various inputs that include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, other observable inputs for the asset or liability and market-corroborated inputs, (i.e., inputs derived principally from or corroborated by observable market data by correlation or other means). Where observable inputs are available for substantially the full term of the asset or liability, the instrument is categorized within Level 2. Level 3- Certain derivatives trade in less active markets with a lower availability of pricing information and models may be utilized in the valuation. When such inputs have a significant impact on the measurement of fair value, the instrument is categorized within Level 3. Credit risk is considered in the fair value calculation of derivative instruments that are not exchange-traded. Credit exposures are adjusted to reflect collateral agreements that reduce exposures. As of December 31, 2021 and 2020, there were no material transfers between fair value hierarchies. Additionally, there were no changes in the method or significant assumptions used to estimate the fair value of our financial instruments. Credit risk is considered in the fair value calculation of each of our forward-starting interest rate swaps, as described in Note 10, "Risk Management Activities." As they are based on observable data and valuations of similar instruments, the hedges are categorized within Level 2 of the fair value hierarchy. There was no exchange of premium at the initial date of the swaps, and we can settle the contracts at any time. NIPSCO has entered into long-term forward natural gas purchase instruments to lock in a fixed price for its natural gas customers. We value these contracts using a pricing model that incorporates market-based information when available, as these instruments trade less frequently and are classified within Level 2 of the fair value hierarchy. For additional information see Note 10, “Risk Management Activities.” Available-for-Sale Debt Securities. Available-for-sale debt securities are investments pledged as collateral for trust accounts related to our wholly-owned insurance company. We value U.S. Treasury, corporate debt and mortgage-backed securities using a matrix pricing model that incorporates market-based information. These securities trade less frequently and are classified within Level 2. Our available-for-sale debt securities impairments are recognized periodically using an allowance approach. At each reporting date, we utilize a quantitative and qualitative review process to assess the impairment of available-for-sale debt securities at the individual security level. For securities in a loss position, we evaluate our intent to sell or whether it is more-likely-than-not that we will be required to sell the security prior to the recovery of its amortized cost. If either criteria is met, the loss is recognized in earnings immediately, with the offsetting entry to the carrying value of the security. If both criteria are not met, we perform an analysis to determine whether the unrealized loss is related to credit factors. The analysis focuses on a variety of factors that include, but are not limited to, downgrade on ratings of the security, defaults in the current reporting period or projected defaults in the future, the security's yield spread over treasuries, and other relevant market data. If the unrealized loss is not related to credit factors, it is included in other comprehensive income. If the unrealized loss is related to credit factors, the loss is recognized as credit loss expense in earnings during the period, with an offsetting entry to the allowance for credit losses. The amount of the credit loss recorded to the allowance account is limited by the amount at which the security's fair value is less than its amortized cost basis. If certain amounts recorded in the allowance for credit losses are deemed uncollectible, the allowance on the uncollectible portion will be charged off, with an offsetting entry to the carrying value of the security. Subsequent improvements to the estimated credit losses of available-for-sale debt securities will be recognized immediately in earnings. As of December 31, 2021 and December 31, 2020, we recorded $0.2 million and $0.5 million, respectively, as an allowance for credit losses on available-for-sale debt securities as a result of the analysis described above. Continuous credit monitoring and portfolio credit balancing mitigates our risk of credit losses on our available-for-sale debt securities. The amortized cost, gross unrealized gains and losses, allowance for credit losses, and fair value of available-for-sale securities at December 31, 2021 and 2020 were: December 31, 2021 (in millions) Amortized Gross Gross Unrealized Losses (1) Allowance for Credit Losses Fair Value Available-for-sale debt securities U.S. Treasury debt securities $ 52.8 $ 0.1 $ (0.4) $ — $ 52.5 Corporate/Other debt securities 116.5 3.7 (0.7) (0.2) 119.3 Total $ 169.3 $ 3.8 $ (1.1) $ (0.2) $ 171.8 December 31, 2020 (in millions) Amortized Gross Gross Unrealized Losses (2) Allowance for Credit Losses Fair Value Available-for-sale debt securities U.S. Treasury debt securities $ 33.7 $ 0.3 $ — $ — $ 34.0 Corporate/Other debt securities 130.2 7.7 (0.5) (0.5) 136.9 Total $ 163.9 $ 8.0 $ (0.5) $ (0.5) $ 170.9 (1) Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $36.2 and $35.4 million, respectively, at December 31, 2021. (2) Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is zero and $13.2 million, respectively, at December 31, 2020. Realized gains and losses on available-for-sale securities were immaterial for the year-ended December 31, 2021 and 2020. The cost of maturities sold is based upon specific identification. At December 31, 2021, approximately $8.2 million of U.S. Treasury debt securities and approximately $3.8 million of Corporate/Other debt securities have maturities of less than a year. There are no material items in the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis for the years ended December 31, 2021 and 2020. Non-recurring Fair Value Measurements We measure the fair value of certain assets, including goodwill, on a non-recurring basis, typically when events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. The sale of the Massachusetts Business occurred on October 9, 2020, and the assets and liabilities of the Massachusetts Business were measured at fair value, less costs to sell. In March 2021, we reached an agreement with Eversource regarding the final purchase price, including net working capital adjustments to the October 9, 2020 purchase price of our Massachusetts Business. The working capital amounts were measured at fair value, less costs to sell. Purchase Contract Liability. At April 19, 2021, we recorded the purchase contract liability at fair value using a discounted cash flow method and observable, market-corroborated inputs. This estimate was made at April 19, 2021, and will not be remeasured at each subsequent balance sheet date. It has been categorized within Level 2 of the fair value hierarchy. Refer to Note 13, ''Equity'' for additional information. B. Other Fair Value Disclosures for Financial Instruments . The carrying amount of cash and cash equivalents, restricted cash, notes receivable, customer deposits and short-term borrowings is a reasonable estimate of fair value due to their liquid or short-term nature. Our long-term borrowings are recorded at historical amounts. The following method and assumptions were used to estimate the fair value of each class of financial instruments. Long-term debt . The fair value of outstanding long-term debt is estimated based on the quoted market prices for the same or similar securities. Certain premium costs associated with the early settlement of long-term debt are not taken into consideration in determining fair value. These fair value measurements are classified within Level 2 of the fair value hierarchy. For the years ended December 31, 2021 and 2020, there was no change in the method or significant assumptions used to estimate the fair value of long-term debt. The carrying amount and estimated fair values of these financial instruments were as follows: At December 31, (in millions) Carrying Amount 2021 Estimated Fair Value 2021 Carrying Amount 2020 Estimated Fair Value 2020 Long-term debt (including current portion) $ 9,241.5 $ 10,415.7 $ 9,243.1 $ 11,034.2

Other Commitments And Contingen

Other Commitments And Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Other Commitments And Contingencies	Other Commitments and Contingencies A. Contractual Obligations . We have certain contractual obligations requiring payments at specified periods. The obligations include long-term debt, lease obligations, energy commodity contracts and obligations for various services including pipeline capacity and outsourcing of IT services. The total contractual obligations in existence at December 31, 2021 and their maturities were: (in millions) Total 2022 2023 2024 2025 2026 After Long-term debt (1) $ 9,135.0 $ 30.0 $ — $ — $ 1,260.0 $ — $ 7,845.0 Interest payments on long-term debt 5,710.0 335.7 334.1 334.1 334.1 321.6 4,050.4 Finance leases (2) 244.3 37.2 33.6 25.6 19.2 15.8 112.9 Operating leases (3) 41.4 7.9 4.9 4.6 4.0 3.8 16.2 Energy commodity contracts 68.6 60.4 8.2 — — — — Service obligations: Pipeline service obligations 1,605.0 610.5 366.0 241.0 136.1 98.7 152.7 IT service obligations 180.1 69.5 44.8 35.7 27.6 2.5 — Other liabilities (4) 553.0 95.6 457.4 — — — — Total contractual obligations $ 17,537.4 $ 1,246.8 $ 1,249.0 $ 641.0 $ 1,781.0 $ 442.4 $ 12,177.2 (1) Long-term debt balance excludes unamortized issuance costs and discounts of $79.1 million. (2) Finance lease payments shown above are inclusive of interest totaling $58.7 million. (3) Operating lease payments shown above are inclusive of interest totaling $6.8 million. Operating lease balances do not include obligations for possible fleet vehicle lease renewals beyond the initial lease term. While we have the ability to renew these leases beyond the initial term, we are not reasonably certain to do so as they are renewed month-to-month after the first year. If we were to continue the fleet vehicle leases outstanding at December 31, 2021, payments would be $33.3 million in 2022, $30.2 million in 2023, $27.2 million in 2024, $24.0 million in 2025, $17.0 million in 2026 and $16.1 million thereafter. (4) Other liabilities shown above are inclusive of the Rosewater and Indiana Crossroads Developer payments due in 2023 and Equity Unit purchase contract liability payments to be made in 2022 and 2023. Purchase and Service Obligations. We have entered into various purchase and service agreements whereby we are contractually obligated to make certain minimum payments in future periods. Our purchase obligations are for the purchase of physical quantities of natural gas, electricity and coal. Our service agreements encompass a broad range of business support and maintenance functions which are generally described below. Our subsidiaries have entered into various energy commodity contracts to purchase physical quantities of natural gas, electricity and coal. These amounts represent the minimum quantity of these commodities we are obligated to purchase at both fixed and variable prices. To the extent contractual purchase prices are variable, obligations disclosed in the table above are valued at market prices as of December 31, 2021. NIPSCO has power purchase arrangements representing a total of 500 MW of wind power, with contracts expiring between 2024 and 2040. No minimum quantities are specified within these agreements due to the variability of electricity generation from wind, so no amounts related to these contracts are included in the table above. Upon early termination of one of these agreements by NIPSCO for any reason (other than material breach by the counterparties), NIPSCO may be required to pay a termination charge that could be material depending on the events giving rise to termination and the timing of the termination. We have pipeline service agreements that provide for pipeline capacity, transportation and storage services. These agreements, which have expiration dates ranging from 2022 to 2038, require us to pay fixed monthly charges. NIPSCO has contracts with three major rail operators providing for coal transportation services for which there are certain minimum payments. These service contracts extend for various periods through 2028. We have executed agreements with multiple IT service providers. The agreements extend for various periods through 2027. B. Guarantees and Indemnities . We and certain of our subsidiaries enter into various agreements providing financial or performance assurance to third parties on behalf of certain subsidiaries as part of normal business. Such agreements include guarantees and stand-by letters of credit. These agreements are entered into primarily to support or enhance the creditworthiness otherwise attributed to a subsidiary on a stand-alone basis, thereby facilitating the extension of sufficient credit to accomplish the subsidiaries’ intended commercial purposes. At December 31, 2021 and 2020, we had issued stand-by letters of credit of $18.9 million and $15.2 million, respectively, for the benefit of third parties. We provide guarantees related to our future performance under BTAs for our renewable generation projects. At December 31, 2021 and 2020, our guarantees for multiple BTAs totaled $288.9 million and $40.7 million, respectively. In February 2022, the amount of the guarantees increased to $485.2 million in accordance with the Fairbanks and Cavalry BTAs. The amount of each guaranty will decrease upon the substantial completion of the construction of the facilities. See “- F. Other Matters - Generation Transition,” below for more information. C. Legal Proceedings . On September 13, 2018, a series of fires and explosions occurred in Lawrence, Andover and North Andover, Massachusetts related to the delivery of natural gas by Columbia of Massachusetts (the "Greater Lawrence Incident"). We have been subject to inquiries and investigations by government authorities and regulatory agencies regarding the Greater Lawrence Incident. On February 26, 2020, the Company and Columbia of Massachusetts entered into agreements with the U.S. Attorney’s Office for the District of Massachusetts to resolve the U.S. Attorney’s Office’s investigation relating to the Greater Lawrence Incident, as described below. The Company and Columbia of Massachusetts entered into an agreement with the Massachusetts Attorney General’s Office (among other parties) to resolve the Massachusetts DPU and the Massachusetts Attorney General’s Office investigations, that was approved by the Massachusetts DPU on October 7, 2020 as part of the sale of the Massachusetts Business to Eversource. U.S. Department of Justice Investigation. On February 26, 2020, the Company and Columbia of Massachusetts entered into agreements with the U.S. Attorney’s Office to resolve the U.S. Attorney’s Office’s investigation relating to the Greater Lawrence Incident. Columbia of Massachusetts agreed to plead guilty in the United States District Court for the District of Massachusetts (the “Court”) to violating the Natural Gas Pipeline Safety Act (the “Plea Agreement”), and the Company entered into a Deferred Prosecution Agreement (the “DPA”). On March 9, 2020, Columbia of Massachusetts entered its guilty plea pursuant to the Plea Agreement. The Court sentenced Columbia of Massachusetts on June 23, 2020, in accordance with the terms of the Plea Agreement (as modified). On June 23, 2021, the Court terminated Columbia of Massachusetts' period of probation under the Plea Agreement, which marked the completion of all terms of the Plea Agreement. Under the DPA, the U.S. Attorney’s Office agreed to defer prosecution of the Company in connection with the Greater Lawrence Incident for a three-year period (which three-year period may be extended for twelve (12) months upon the U.S. Attorney’s Office’s determination of a breach of the DPA) subject to certain obligations of the Company, including, but not limited to, the Company's agreement, as to each of the Company’s subsidiaries involved in the distribution of gas through pipeline facilities in Massachusetts, Indiana, Ohio, Pennsylvania, Maryland, Kentucky and Virginia to implement and adhere to each of the recommendations from the NTSB stemming from the Greater Lawrence Incident. Pursuant to the DPA, if the Company complies with all of its obligations under the DPA, the U.S. Attorney’s Office will not file any criminal charges against the Company related to the Greater Lawrence Incident. Private Actions. Various lawsuits, including several purported class action lawsuits, were filed by various affected residents or businesses in Massachusetts state courts against the Company and/or Columbia of Massachusetts in connection with the Greater Lawrence Incident. On March 12, 2020, the Court granted final approval of the settlement of the consolidated class action. With respect to claims not included in the consolidated class action, many of the asserted wrongful death and bodily injury claims have settled, and we continue to discuss potential settlements with remaining claimants. The outcomes and impacts of such private actions are uncertain at this time. Shareholder Derivative Lawsuit. On April 28, 2020, a shareholder derivative lawsuit was filed by the City of Detroit Police and Fire Retirement System in the United States District Court for the District of Delaware against certain of the Company's current and former directors, alleging state-law claims for breaches of fiduciary duty with respect to the pipeline safety management systems relating to the distribution of natural gas prior to the Greater Lawrence Incident and also including federal-law claims related to our proxy statement disclosures regarding our safety systems. The remedies sought included damages for the alleged breaches of fiduciary duty, corporate governance reforms, and restitution of any unjust enrichment. The defendants filed a motion to dismiss the lawsuit and oral argument was held on March 2, 2021. On March 9, 2021, the district court granted the defendants’ motion to dismiss. It dismissed the federal-law claims with prejudice for failure to state a claim on which relief can be granted and declined to exercise jurisdiction over the state-law claims, which were dismissed without prejudice. Following the dismissal of the federal court action, on April 29, 2021, the same plaintiff filed a shareholder derivative lawsuit in the Delaware Court of Chancery against certain of our current and former directors. The new complaint alleged a single count for breach of fiduciary duty, and no longer alleged disclosure violations or breaches of federal securities laws. The complaint related to substantially the same matters as those alleged in the dismissed federal derivative complaint. The remedies sought included damages for the alleged breaches of fiduciary duty, corporate governance reforms, and restitution of compensation by the individual defendants. On May 19, 2021, the defendants filed a motion to dismiss the lawsuit, and on July 2, 2021, they filed their opening brief in support of the motion. On August 26, 2021, rather than respond to the defendants’ motion to dismiss and opening brief, the plaintiff filed an amended complaint. Like the original complaint in the Delaware Court of Chancery, the amended complaint alleges a single count for breach of fiduciary duty, based on substantially similar allegations, and seeks substantially similar remedies. On September 10, 2021, the defendants filed a motion to dismiss. Briefing on the defendants' motion to dismiss was completed on January 10, 2022, and oral argument on the defendants' motion to dismiss took place on February 3, 2022. Because of the preliminary nature of this lawsuit, we are not able to estimate a loss or range of loss, if any, that may be incurred in connection with this matter at this time. Other Claims and Proceedings. We are also party to certain other claims, regulatory and legal proceedings arising in the ordinary course of business in each state in which we have operations, none of which we believe to be individually material at this time. Due to the inherent uncertainty of litigation, there can be no assurance that the resolution of any particular claim, proceeding or investigation would not have a material adverse effect on our results of operations, financial position or liquidity. If one or more other matters were decided against us, the effects could be material to our results of operations in the period in which we would be required to record or adjust the related liability and could also be material to our cash flows in the periods that we would be required to pay such liability. D. Other Greater Lawrence Incident Matters . In connection with the Greater Lawrence Incident, Columbia of Massachusetts, in cooperation with the Massachusetts Governor’s office, replaced the entire affected pipeline system. We invested approximately $258 million of capital spend for the pipeline replacement; this work was completed in 2019. We maintain property insurance for gas pipelines and other applicable property. Columbia of Massachusetts has filed a proof of loss with its property insurer for the pipeline replacement. In January 2020, we filed a lawsuit against the property insurer, seeking payment of our property claim. On October 27, 2021, NiSource and the property insurer filed cross motions for summary judgment, each asking the court to determine whether there was coverage under the policy. After the cross motions for summary judgment were fully briefed, we reached an agreement in principle to settle the coverage dispute for a portion of the above invested amount. We expect that the agreement will be finalized, a settlement payment by the insurer to NiSource will be made, and the case will be dismissed by the end of the first quarter of 2022. E. Environmental Matters . Our operations are subject to environmental statutes and regulations related to air quality, water quality, hazardous waste and solid waste. We believe that we are in substantial compliance with the environmental regulations currently applicable to our operations. It is management's continued intent to address environmental issues in cooperation with regulatory authorities in such a manner as to achieve mutually acceptable compliance plans. However, there can be no assurance that fines and penalties will not be incurred. Management expects a majority of environmental assessment and remediation costs and asset retirement costs, further described below, to be recoverable through rates. See Note 9, "Regulatory Matters," for additional detail. As of December 31, 2021 and 2020, we had recorded a liability of $91.1 million and $92.6 million, respectively, to cover environmental remediation at various sites. This liability is included in "Other accruals" and "Other noncurrent liabilities" in the Consolidated Balance Sheets. We recognize costs associated with environmental remediation obligations when the incurrence of such costs is probable and the amounts can be reasonably estimated. The original estimates for remediation activities may differ materially from the amount ultimately expended. The actual future expenditures depend on many factors, including laws and regulations, the nature and extent of impact and the method of remediation. These expenditures are not currently estimable at some sites. We periodically adjust our liability as information is collected and estimates become more refined. See Note 8, "Asset Retirement Obligations," for a discussion of all obligations, including those discussed below. CERCLA. Our subsidiaries are potentially responsible parties at waste disposal sites under the CERCLA and similar state laws. Under CERCLA, each potentially responsible party can be held jointly, severally and strictly liable for the remediation costs as the EPA, or state, can allow the parties to pay for remedial action or perform remedial action themselves and request reimbursement from the potentially responsible parties. Our affiliates have retained CERCLA environmental liabilities, including remediation liabilities, associated with certain current and former operations. At this time, NIPSCO cannot estimate the full cost of remediating properties that have not yet been investigated, but it is possible that the future costs could be material to the Consolidated Financial Statements. MGP. We maintain a program to identify and investigate former MGP sites where Gas Distribution Operations subsidiaries or predecessors may have liability. The program has identified 54 such sites where liability is probable. Remedial actions at many of these sites are being overseen by state or federal environmental agencies through consent agreements or voluntary remediation agreements. We utilize a probabilistic model to estimate our future remediation costs related to MGP sites. The model was prepared with the assistance of a third party and incorporates our experience and general industry experience with remediating MGP sites. We complete an annual refresh of the model in the second quarter of each fiscal year. No material changes to the estimated future remediation costs were noted as a result of the refresh completed as of June 30, 2021. Our total estimated liability related to the facilities subject to remediation was $85.1 million and $85.0 million at December 31, 2021 and 2020, respectively. The liability represents our best estimate of the probable cost to remediate the MGP sites. We believe that it is reasonably possible that remediation costs could vary by as much as $17 million in addition to the costs noted above. Remediation costs are estimated based on the best available information, applicable remediation standards at the balance sheet date, and experience with similar facilities. CCRs. We are in compliance with the EPA's final rule for the regulation of CCRs. The CCR rule also resulted in revisions to previously recorded legal obligations associated with the retirement of certain NIPSCO facilities. The actual asset retirement costs related to the CCR rule may vary substantially from the estimates used to record the increased asset retirement obligation due to the uncertainty about the requirements that will be established by environmental authorities, compliance strategies that will be used and the preliminary nature of available data used to estimate costs. As allowed by the rule, NIPSCO will continue to collect data over time to determine the specific compliance solutions and associated costs and, as a result, the actual costs may vary. NIPSCO will also continue to work with the EPA and the Indiana Department of Environmental Management to obtain administrative approvals associated with the CCR rule. In the event that the approvals are not obtained, future operations could be impacted. We cannot estimate the likelihood that the agencies will deny approvals or the financial impact on us if these approvals are not obtained. F. Other Matters. Generation Transition. NIPSCO has executed several PPAs to purchase 100% of the output from renewable generation facilities at a fixed price per MWh. Each facility supplying the energy will have an associated nameplate capacity, and payments under the PPAs will not begin until the associated generation facility is constructed by the owner/seller. NIPSCO has also executed several BTAs with developers to construct renewable generation facilities. NIPSCO's purchase obligation under each respective BTAs is dependent on satisfactory approval of the BTA by the IURC, successful execution by NIPSCO of an agreement with a tax equity partner and timely completion of construction. NIPSCO has received IURC approval for all of its BTAs and PPAs. NIPSCO and the tax equity partner are obligated to make cash contributions to the joint venture that acquires the project at the date construction is substantially complete. Once the tax equity partner has earned its negotiated rate of return and we have reached the agreed upon contractual date, NIPSCO has the option to purchase at fair market value from the tax equity partner the remaining interest in the joint venture. Employee Separation Benefits. In the third quarter of 2020, we launched a program to evaluate our organizational structure under the auspices of NiSource Next, which has continued into 2021. We recognized the majority of the related severance expense in 2020 when the employees accepted severance offers, absent a retention period. For employees that have a retention period, expense will be recognized over the remaining service period. The total severance expense for employees is approximately $42 million, with substantially all of it incurred and paid to date.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2021
Components of Accumulated Other Comprehensive Income (Loss) [Abstract]
Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss The following table displays the activity of Accumulated Other Comprehensive Loss, net of tax: (in millions) Gains and Losses on Securities (1) Gains and Losses on Cash Flow Hedges (1) Pension and OPEB Items (1) Accumulated Other Comprehensive Loss (1) Balance as of January 1, 2019 $ (2.4) $ (13.0) $ (21.8) $ (37.2) Other comprehensive income (loss) before reclassifications 6.1 (64.3) 2.3 (55.9) Amounts reclassified from accumulated other comprehensive loss (0.4) 0.1 0.8 0.5 Net current-period other comprehensive income (loss) 5.7 (64.2) 3.1 (55.4) Balance as of December 31, 2019 $ 3.3 $ (77.2) $ (18.7) $ (92.6) Other comprehensive income (loss) before reclassifications 3.3 (70.8) 2.9 (64.6) Amounts reclassified from accumulated other comprehensive loss (0.6) 0.1 1.0 0.5 Net current-period other comprehensive income (loss) 2.7 (70.7) 3.9 (64.1) Balance as of December 31, 2020 $ 6.0 $ (147.9) $ (14.8) $ (156.7) Other comprehensive income (loss) before reclassifications (3.5) 25.3 6.6 28.4 Amounts reclassified from accumulated other comprehensive loss (0.4) 0.1 1.8 1.5 Net current-period other comprehensive income (loss) (3.9) 25.4 8.4 29.9 Balance as of December 31, 2021 $ 2.1 $ (122.5) $ (6.4) $ (126.8) (1) All amounts are net of tax. Amounts in parentheses indicate debits.

Other, Net

Other, Net	12 Months Ended
	Dec. 31, 2021
Other Nonoperating Income (Expense) [Abstract]
Other, Net	Other, Net Year Ended December 31, (in millions) 2021 2020 2019 Interest income $ 4.0 $ 5.5 $ 7.7 AFUDC equity 13.1 9.9 8.0 Charitable contributions (11.5) (1.5) (5.1) Pension and other postretirement non-service cost (1) 35.5 9.3 (16.5) Sale of emission reduction credits — 4.6 — Miscellaneous (0.3) 4.3 0.7 Total Other, net $ 40.8 $ 32.1 $ (5.2) (1) See Note 12, "Pension and Other Postretirement Benefits" for additional information.

Interest Expense, Net

Interest Expense, Net	12 Months Ended
	Dec. 31, 2021
Interest Expense [Abstract]
Interest Expense, Net	Interest Expense, Net Year Ended December 31, (in millions) 2021 2020 2019 Interest on long-term debt $ 336.4 $ 354.2 $ 327.7 Interest on short-term borrowings 0.6 14.7 50.8 Debt discount/cost amortization 11.0 9.1 8.3 Accounts receivable securitization fees 1.4 2.6 2.6 Allowance for borrowed funds used and interest capitalized during construction (4.6) (7.0) (7.5) Debt-based post-in-service carrying charges (14.7) (14.6) (18.7) Other 11.0 11.7 15.7 Total Interest Expense, net $ 341.1 $ 370.7 $ 378.9

Segments Of Business

Segments Of Business	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Segments Of Business	Segments of Business At December 31, 2021, our operations are divided into two primary reportable segments, the Gas Distribution Operations and the Electric Operations segments. The remainder of our operations, which are not significant enough on a stand-alone basis to warrant treatment as an operating segment, are presented as "Corporate and Other" and primarily are comprised of interest expense on holding company debt, and unallocated corporate costs and activities. Refer to Note 3, "Revenue Recognition," for additional information on our segments and their sources of revenues. The following table provides information about our reportable segments. We use operating income as our primary measurement for each of the reported segments and make decisions on finance, dividends and taxes at the corporate level on a consolidated basis. Segment revenues include intersegment sales to affiliated subsidiaries, which are eliminated in consolidation. Affiliated sales are recognized on the basis of prevailing market, regulated prices or at levels provided for under contractual agreements. Operating income is derived from revenues and expenses directly associated with each segment. Year Ended December 31, (in millions) 2021 2020 2019 Operating Revenues Gas Distribution Operations Unaffiliated $ 3,171.2 $ 3,128.1 $ 3,509.7 Intersegment 12.3 12.1 13.1 Total 3,183.5 3,140.2 3,522.8 Electric Operations Unaffiliated 1,696.3 1,535.9 1,698.4 Intersegment 0.8 0.7 0.8 Total 1,697.1 1,536.6 1,699.2 Corporate and Other Unaffiliated 32.1 17.7 0.8 Intersegment 460.3 449.8 468.1 Total 492.4 467.5 468.9 Eliminations (473.4) (462.6) (482.0) Consolidated Operating Revenues $ 4,899.6 $ 4,681.7 $ 5,208.9 Year Ended December 31, (in millions) 2021 2020 2019 Operating Income (Loss) Gas Distribution Operations (1) $ 617.5 $ 199.1 $ 675.4 Electric Operations 387.8 348.8 406.8 Corporate and Other (2) 1.6 2.9 (191.5) Consolidated Operating Income $ 1,006.9 $ 550.8 $ 890.7 Depreciation and Amortization Gas Distribution Operations $ 383.0 $ 363.1 $ 403.2 Electric Operations 329.4 321.3 277.3 Corporate and Other 36.0 41.5 36.9 Consolidated Depreciation and Amortization $ 748.4 $ 725.9 $ 717.4 Assets Gas Distribution Operations $ 15,153.7 $ 13,433.0 $ 14,224.5 Electric Operations 7,178.9 6,443.1 6,027.6 Corporate and Other 1,824.3 2,164.4 2,407.7 Consolidated Assets $ 24,156.9 $ 22,040.5 $ 22,659.8 Capital Expenditures (3) Gas Distribution Operations $ 1,406.4 $ 1,266.9 $ 1,380.3 Electric Operations 517.4 422.8 468.9 Corporate and Other 16.6 31.1 18.6 Consolidated Capital Expenditures $ 1,940.4 $ 1,720.8 $ 1,867.8 (1) In 2020, Gas Distribution Operations reflects the loss of $412.4 million on the sale of the Massachusetts Business. (2) In 2019, Corporate and Other reflects an impairment charge of $204.8 million for goodwill related to Columbia of Massachusetts. For additional information, see Note 7, "Goodwill and Other Intangible Assets." (3) Amounts differ from those presented on the Statements of Consolidated Cash Flows primarily due to the inclusion of capital expenditures in current liabilities, the capitalized portion of the Corporate Incentive Plan payout, and AFUDC Equity.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	12 Months Ended
	Dec. 31, 2021
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information The following table provides additional information regarding our Consolidated Statements of Cash Flows for the years ended December 31, 2021, 2020 and 2019: Year Ended December 31, (in millions) 2021 2020 2019 Supplemental Disclosures of Cash Flow Information Non-cash transactions: Capital expenditures included in current liabilities $ 245.7 $ 170.4 $ 223.6 Assets acquired under a finance lease 22.4 59.3 26.4 Assets acquired under an operating lease 6.0 10.9 13.4 Reclassification of other property to regulatory assets (1) 607.6 — — Assets recorded for asset retirement obligations (2) 12.0 91.5 54.6 Obligation to developer at formation of joint venture (3) 277.5 69.7 — Purchase contract liability, net of fees and payments (4) 129.4 — — Schedule of interest and income taxes paid: Cash paid for interest on long-term debt, net of interest capitalized amounts $ 322.4 $ 349.0 $ 349.7 Cash paid for interest on finance leases 9.4 11.1 11.3 Cash paid for income taxes, net of refunds (5) 5.4 (1.0) 10.8 (1) See Note 9, "Regulatory Matters," for additional information. (2) See Note 8, "Asset Retirement Obligations," for additional information. (3) Represents investing non-cash activity. See Note 4, "Variable Interest Entities," for additional information. (4) Refer to Note 13, "Equity," for additional information. (5) Amount of refunds in 2020 was greater than the amount of tax payments due to overpayments in 2019.

Nature of Operations And Summ_2

Nature of Operations And Summary of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Company Structure And Principles Of Consolidation	Company Structure and Principles of Consolidation. We are an energy holding company incorporated in Delaware and headquartered in Merrillville, Indiana. Our subsidiaries are fully regulated natural gas and electric utility companies serving approximately 3.7 million customers in six states. We generate substantially all of our operating income through these rate-regulated businesses. The consolidated financial statements include the accounts of us, our majority-owned subsidiaries, and VIEs of which we are the primary beneficiary after the elimination of all intercompany accounts and transactions.
Use Of Estimates	Use of Estimates. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Cash, Cash Equivalents, And Restricted Cash	Cash, Cash Equivalents and Restricted Cash. We consider all highly liquid investments with original maturities of three months or less to be cash equivalents. We report amounts deposited in brokerage accounts for margin requirements as restricted cash. In addition, we have amounts deposited in trusts to satisfy requirements for the provision of various property, liability, workers compensation, and long-term disability insurance, which is classified as restricted cash on the Consolidated Balance Sheets and disclosed with cash and cash equivalents on the Statements of Consolidated Cash Flows.
Accounts Receivable And Unbilled Revenue	Accounts Receivable and Unbilled Revenue. Accounts receivable on the Consolidated Balance Sheets includes both billed and unbilled amounts. Unbilled amounts of accounts receivable relate to a portion of a customer’s consumption of gas or electricity from the last cycle billing date through the last day of the month (balance sheet date). Factors taken into consideration when estimating unbilled revenue include historical usage, customer rates, weather and reasonable and supportable forecasts. Accounts receivable fluctuates from year to year depending in large part on weather impacts and price volatility. Our accounts receivable on the Consolidated Balance Sheets include unbilled revenue, less reserves. The reserve for uncollectible receivables is our best estimate of the amount of probable credit losses in the existing accounts receivable. We determined the reserve based on historical experience and in consideration of current market conditions. Account balances are charged against the allowance when it is anticipated the receivable will not be recovered. Refer to Note 3, "Revenue Recognition," for additional information on customer-related accounts receivable, including amounts related to unbilled revenues.
Investments In Debt And Equity Securities	Investments in Debt Securities. Our investments in debt securities are carried at fair value and are designated as available-for-sale. These investments are included within “Available-for-sale debt securities” on the Consolidated Balance Sheets. Unrealized gains and losses, net of deferred income taxes, are recorded to accumulated other comprehensive income or loss. At each reporting period these investments are qualitatively and quantitatively assessed to determine whether a decline in fair value below the amortized cost basis has resulted from a credit loss or other factors. Impairments related to credit loss are recorded through an allowance for credit losses. Impairments that are not related to credit losses are included in other comprehensive income and are reflected in the Statements of Consolidated Income (Loss). No material impairment charges were recorded for the years ended December 31, 2021, 2020 or 2019. Refer to Note 18, "Fair Value," for additional information.
Basis Of Accounting For Rate-Regulated Subsidiaries	Basis of Accounting for Rate-Regulated Subsidiaries. Rate-regulated subsidiaries account for and report assets and liabilities consistent with the economic effect of the way in which regulators establish rates, if the rates established are designed to recover the costs of providing the regulated service and it is probable that such rates can be charged and collected. Certain expenses and credits subject to utility regulation or rate determination normally reflected in income are deferred on the Consolidated Balance Sheets and are later recognized in income as the related amounts are included in customer rates and recovered from or refunded to customers.We continually evaluate whether or not our operations are within the scope of ASC 980 and rate regulations. As part of that analysis, we evaluate probability of recovery for our regulatory assets. In management’s opinion, our regulated subsidiaries will be subject to regulatory accounting for the foreseeable future. Refer to Note 9, "Regulatory Matters," for additional information.
Utility Plant And Other Property And Related Depreciation And Maintenance	Plant and Other Property and Related Depreciation and Maintenance. Property, plant and equipment (principally utility plant) is stated at cost. Our rate-regulated subsidiaries record depreciation using composite rates on a straight-line basis over the remaining service lives of the electric, gas and common properties, as approved by the appropriate regulators. Non-utility property includes renewable generation assets owned by joint ventures of which we are the primary beneficiary and is generally depreciated on a straight-line basis over the life of the associated assets. Refer to Note 6, "Property, Plant and Equipment," for additional information related to depreciation expense. For rate-regulated companies, AFUDC is capitalized on all classes of property except organization costs, land, autos, office equipment, tools and other general property purchases. The allowance is applied to construction costs for that period of time between the date of the expenditure and the date on which such project is placed in service. Our pre-tax rate for AFUDC was 3.3% in 2021, 2.6% in 2020 and 3.0% in 2019. Generally, our subsidiaries follow the practice of charging maintenance and repairs, including the cost of removal of minor items of property, to expense as incurred. When our subsidiaries retire regulated property, plant and equipment, original cost plus the cost of retirement, less salvage value, is charged to accumulated depreciation. However, when it becomes probable a regulated asset will be retired substantially in advance of its original expected useful life or is abandoned, the cost of the asset and the corresponding accumulated depreciation is recognized as a separate asset. If the asset is still in operation, the gross amounts are classified as "Non-Utility and Other " as described in Note 6, "Property, Plant and Equipment." If the asset is no longer operating but still subject to recovery, the net amount is classified in "Regulatory assets" on the Consolidated Balance Sheets. If we are able to recover a full return of and on investment, the carrying value of the asset is based on historical cost. If we are not able to recover a full return on investment, a loss on impairment is recognized to the extent the net book value of the asset exceeds the present value of future revenues discounted at the incremental borrowing rate. When our subsidiaries sell entire regulated operating units, or retire or sell nonregulated properties, the original cost and accumulated depreciation and amortization balances are removed from "Net Property, Plant and Equipment" on the Consolidated Balance Sheets. Any gain or loss is recorded in earnings, unless otherwise required by the applicable regulatory body. Refer to Note 6, "Property, Plant and Equipment," for further information.
Goodwill And Other Intangible Assets	Goodwill and Other Intangible Assets. Substantially all of our goodwill relates to the excess of cost over the fair value of the net assets acquired in the Columbia acquisition on November 1, 2000. We test our goodwill for impairment annually as of May 1, or more frequently if events and circumstances indicate that goodwill might be impaired. Fair value of our reporting units is determined using a combination of income and market approaches. See Note 7, "Goodwill and Other Intangible Assets," for additional information.
Accounts Receivable Transfer Program	Accounts Receivable Transfer Program. Certain of our subsidiaries have agreements with third parties to transfer certain accounts receivable without recourse. These transfers of accounts receivable are accounted for as secured borrowings. The entire gross receivables balance remains on the December 31, 2021 and 2020 Consolidated Balance Sheets. When amounts are securitized, the short-term debt is recorded in the amount of proceeds received from the transferees involved in the transactions. Refer to Note 16, "Short Term Borrowings," for further information.
Fuel Adjustment Clause	Gas Cost and Fuel Adjustment Clause. Our regulated subsidiaries defer most differences between gas and fuel purchase costs and the recovery of such costs in revenues and adjust future billings for such deferrals on a basis consistent with applicable state-approved tariff provisions. These deferred balances are recorded as "Regulatory assets" or "Regulatory liabilities," as appropriate, on the Consolidated Balance Sheets. Refer to Note 9, "Regulatory Matters," for additional information.
Gas Inventory	Inventory. Both the LIFO inventory methodology and the weighted average cost methodology are used to value natural gas in storage, as approved by regulators for all of our regulated subsidiaries. Inventory valued using LIFO was $44.9 million and $42.3 million at December 31, 2021 and 2020, respectively. Based on the average cost of gas using the LIFO method, the estimated replacement cost of gas in storage was less than the stated LIFO cost by $13.6 million and $19.6 million at December 31, 2021 and 2020, respectively. As all LIFO inventory costs are collected from customers through our rate- regulated subsidiaries, no inventory impairment has been recorded. Gas inventory valued using the weighted average cost methodology was $282.4 million at December 31, 2021 and $148.8 million at December 31, 2020. Electric production fuel is valued using the weighted average cost inventory methodology, as approved by NIPSCO's regulator.
Accounting For Exchange And Balancing Arrangements Of Natural Gas	Accounting for Exchange and Balancing Arrangements of Natural Gas. Our Gas Distribution Operations segment enters into balancing and exchange arrangements of natural gas as part of its operations and off-system sales programs. We record a receivable or payable for any of our respective cumulative gas imbalances, as well as for any gas inventory borrowed or lent under a Gas Distribution Operations exchange agreement. Exchange gas is valued based on individual regulatory jurisdiction requirements (for example, historical spot rate, spot at the beginning of the month). These receivables and payables are recorded as “Exchange gas receivable” or “Exchange gas payable” on our Consolidated Balance Sheets, as appropriate.
Accounting For Risk Management Activities	Accounting for Risk Management Activities. We account for our derivatives and hedging activities in accordance with ASC 815. We recognize all derivatives as either assets or liabilities on the Consolidated Balance Sheets at fair value, unless such contracts are exempted as a normal purchase normal sale under the provisions of the standard. The accounting for changes in the fair value of a derivative depends on the intended use of the derivative and resulting designation. We do not offset the fair value amounts recognized for any of our derivative instruments against the fair value amounts recognized for the right to reclaim cash collateral or obligation to return cash collateral for derivative instruments executed with the same counterparty under a master netting arrangement. See Note 10, "Risk Management Activities," for additional information.
Income Taxes And Investment Tax Credits	Income Taxes and Investment Tax Credits. We record income taxes to recognize full interperiod tax allocations. Under the asset and liability method, deferred income taxes are provided for the tax consequences of temporary differences by applying enacted statutory tax rates applicable to future years to differences between the financial statement carrying amount and the tax basis of existing assets and liabilities. Investment tax credits associated with regulated operations are deferred and amortized as a reduction to income tax expense over the estimated useful lives of the related properties.
Environmental Expenditures	Environmental Expenditures. We accrue for costs associated with environmental remediation obligations, including expenditures related to asset retirement obligations and cost of removal, when the incurrence of such costs is probable and the amounts can be reasonably estimated, regardless of when the expenditures are actually made. The undiscounted estimated future expenditures are based on currently enacted laws and regulations, existing technology and estimated site-specific costs where assumptions may be made about the nature and extent of site contamination, the extent of cleanup efforts, costs of alternative cleanup methods and other variables. The liability is adjusted as further information is discovered or circumstances change. The accruals for estimated environmental expenditures are recorded on the Consolidated Balance Sheets in “Other accruals” for short-term portions of these liabilities and “Other noncurrent liabilities” for the respective long-term portions of these liabilities. Rate-regulated subsidiaries applying regulatory accounting establish regulatory assets on the Consolidated Balance Sheets to the extent that future recovery of environmental remediation costs is probable through the regulatory process. Refer to Note 8, "Asset Retirement Obligations," and Note 19, "Other Commitments and Contingencies," for further information.
Excise Taxes	Excise Taxes. As an agent for some state and local governments, we invoice and collect certain excise taxes levied by state and local governments on customers and record these amounts as liabilities payable to the applicable taxing jurisdiction. Such balances are presented within "Other accruals" on the Consolidated Balance Sheets. These types of taxes collected from customers, comprised largely of sales taxes, are presented on a net basis affecting neither revenues nor cost of sales. We account for excise taxes for which we are liable by recording a liability for the expected tax with a corresponding charge to “Other taxes” expense on the Statements of Consolidated Income (Loss).
Accrued Insurance Liabilities	Accrued Insurance Liabilities. We accrue for insurance costs related to workers compensation, automobile, property, general and employment practices liabilities based on the most probable value of each claim. In general, claim values are determined by professional, licensed loss adjusters who consider the facts of the claim, anticipated indemnification and legal expenses, and respective state rules. Claims are reviewed by us at least quarterly and an adjustment is made to the accrual based on the most current information.
Pension Remeasurement	Pension Remeasurement. We utilize a third-party actuary for the purpose of performing actuarial valuations of our defined benefit plans. Annually, as of December 31, we perform a remeasurement for our pension plans. Quarterly, we monitor for significant events, and if a significant event is identified, we perform a qualitative and quantitative assessment to determine if the resulting remeasurement would materially impact the NiSource financial statements. If material, an interim remeasurement is performed. We had one such interim remeasurement in the first quarter of 2021. See Note 12, "Pension and Other Postretirement Benefits," for additional information.
VIEs and Allocation of Earnings	VIEs and Allocation of Earnings. We fund a significant portion of our renewable generation assets through joint ventures with tax equity partners. We consolidate these joint ventures in accordance with ASC 810 as they are VIEs in which we hold a variable interest, and we control decisions that are significant to the joint ventures' ongoing operations and economic results (i.e., we are the primary beneficiary). These joint ventures are subject to profit sharing arrangements in which the allocation of the joint ventures' cash distributions and tax benefits to members is based on factors other than members' relative ownership percentages. As such, we utilize the HLBV method to allocate proceeds to each partner at the balance sheet date based on the liquidation provisions of the related joint venture's operating agreement and adjusts the amount of the VIE's net income attributable to us and the noncontrolling tax equity member during the period. In each reporting period, the application of HLBV to our consolidated VIEs results in a difference between the amount of profit from the consolidated joint ventures and the amount included in regulated rates. As discussed above in "F. Basis of Accounting for Rate-Regulated Subsidiaries," we are subject to the accounting and reporting requirements of ASC 980. In accordance with these principles, we recognize a regulatory liability or asset for amounts representing the timing difference between the profit earned from the joint ventures and the amount included in regulated rates to recover our approved investments in consolidated joint ventures. The amounts recorded in income will ultimately reflect the amount allowed in regulated rates to recover our investments over the useful life of the projects. The offset to the regulatory liability or asset associated with our renewable investments included in regulated rates is recorded in "Depreciation expense" on the Statements of Consolidated Income (Loss).

Revenue Recognition (Tables)

Revenue Recognition (Tables)	12 Months Ended
	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The tables below reconcile revenue disaggregation by customer class to segment revenue as well as to revenues reflected on the Statements of Consolidated Income (Loss): Year Ended December 31, 2021 (in millions) Gas Distribution Operations Electric Operations Corporate and Other (2) Total Customer Revenues (1) Residential $ 2,109.4 $ 567.9 $ — $ 2,677.3 Commercial 722.4 534.9 — 1,257.3 Industrial 195.7 493.4 — 689.1 Off-system 71.3 — — 71.3 Miscellaneous 27.3 8.2 0.8 36.3 Total Customer Revenues $ 3,126.1 $ 1,604.4 $ 0.8 $ 4,731.3 Other Revenues 45.1 91.9 31.3 168.3 Total Operating Revenues $ 3,171.2 $ 1,696.3 $ 32.1 $ 4,899.6 (1) Customer revenue amounts exclude intersegment revenues. See Note 23, "Segments of Business," for discussion of intersegment revenues. (2) Other revenues related to the Transition Services Agreement entered into in connection with the sale of the Massachusetts Business. Year Ended December 31, 2020 (in millions) Gas Distribution Operations Electric Operations Corporate and Other (2) Total Customer Revenues (1) Residential $ 2,075.0 $ 527.8 $ — $ 2,602.8 Commercial 670.5 480.3 — 1,150.8 Industrial 212.8 412.1 — 624.9 Off-system 41.0 — — 41.0 Miscellaneous 32.7 20.2 0.8 53.7 Total Customer Revenues $ 3,032.0 $ 1,440.4 $ 0.8 $ 4,473.2 Other Revenues 96.1 95.5 16.9 208.5 Total Operating Revenues $ 3,128.1 $ 1,535.9 $ 17.7 $ 4,681.7 (1) Customer revenue amounts exclude intersegment revenues. See Note 23, "Segments of Business," for discussion of intersegment revenues. (2) Other revenues related to the Transition Services Agreement entered into in connection with the sale of the Massachusetts Business. Year Ended December 31, 2019 (in millions) Gas Distribution Operations Electric Operations Corporate and Other Total Customer Revenues (1) Residential $ 2,309.0 $ 481.6 $ — $ 2,790.6 Commercial 771.3 486.6 — 1,257.9 Industrial 245.2 607.7 — 852.9 Off-system 77.7 — — 77.7 Miscellaneous 52.0 21.5 0.8 74.3 Total Customer Revenues $ 3,455.2 $ 1,597.4 $ 0.8 $ 5,053.4 Other Revenues 54.5 101.0 — 155.5 Total Operating Revenues $ 3,509.7 $ 1,698.4 $ 0.8 $ 5,208.9 (1) Customer revenue amounts exclude intersegment revenues. See Note 23, "Segments of Business," for discussion of intersegment revenues.
Customer Accounts Receivable	The opening and closing balances of customer receivables for the year ended December 31, 2021, are presented in the table below. We had no significant contract assets or liabilities during the period. Additionally, we have not incurred any significant costs to obtain or fulfill contracts. (in millions) Customer Accounts Receivable, Billed (less reserve) Customer Accounts Receivable, Unbilled (less reserve) Balance as of December 31, 2020 $ 400.0 $ 327.2 Balance as of December 31, 2021 459.6 337.0
Financing Receivable, Allowance for Credit Loss	A rollforward of our allowance for credit losses as of December 31, 2021 and December 31, 2020, are presented in the tables below: (in millions) Gas Distribution Operations Electric Operations Corporate and Other Total Balance as of January 1, 2021 $ 41.8 $ 9.7 $ 0.8 $ 52.3 Current period provisions 5.8 1.4 — 7.2 Write-offs charged against allowance (46.7) (7.7) — (54.4) Recoveries of amounts previously written off 18.0 0.4 — 18.4 Balance as of December 31, 2021 $ 18.9 $ 3.8 $ 0.8 $ 23.5 (in millions) Gas Distribution Operations Electric Operations Corporate and Other Total Balance as of January 1, 2020 $ 9.1 $ 3.1 $ 0.8 $ 13.0 Current period provisions 45.3 9.3 — 54.6 Write-offs charged against allowance (26.7) (3.0) — (29.7) Recoveries of amounts previously written off 14.1 0.3 — 14.4 Balance as of December 31, 2020 $ 41.8 $ 9.7 $ 0.8 $ 52.3

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2021
Variable Interest Entities [Abstract]
Variable Interest Entities Assets and Liabilities	Our Consolidated Balance Sheets included the following assets and liabilities associated with VIEs. (in millions) December 31, 2021 December 31, 2020 Rosewater Indiana Crossroads Wind Rosewater Indiana Crossroads Wind Net Property, Plant and Equipment $ 170.1 $ 525.8 $ 175.6 $ — Current assets 6.2 8.1 1.7 — Total assets (1) 176.3 533.9 177.3 — Current liabilities 2.5 7.5 15.3 — Asset retirement obligations 5.7 14.8 5.5 — Other noncurrent liabilities — — 0.1 — Total liabilities $ 8.2 $ 22.3 $ 20.9 $ — (1) The assets of Rosewater and Indiana Crossroads represent assets of a consolidated VIE that can be used only to settle obligations of the respective consolidated VIE. The creditors of the liabilities of Rosewater and Indiana Crossroads do not have recourse to the general credit of the primary beneficiary.
Redeemable Noncontrolling Interest	The following table displays the Noncontrolling interest in consolidated subsidiaries included in the Consolidated Balance Sheets: (in millions) December 31, 2021 December 31, 2020 Rosewater $ 88.2 $ 85.6 Indiana Crossroads Wind 237.4 — Total $ 325.6 $ 85.6
Income Amounts Attributable to Noncontrolling Interest	The following table displays the Net income (loss) attributable to noncontrolling interest included in the Statements of Consolidated Income (Loss) for the years ended December 31: (in millions) 2021 2020 2019 Rosewater $ (4.2) $ 3.4 $ — Indiana Crossroads Wind 8.1 — — Total $ 3.9 $ 3.4 $ —
Noncontrolling Interest Cash Contributions	The following table displays the contributions associated with each VIE: (in millions) December 31, 2021 December 31, 2020 Rosewater Indiana Crossroads Wind Rosewater Indiana Crossroads Wind NIPSCO Cash Contribution $ 0.1 $ 2.7 $ 0.7 $ — Tax Equity Partner Cash Contribution 7.5 237.6 86.1 — NIPSCO's Obligation to Developer (1) 6.0 271.5 69.7 — Total Contributions $ 13.6 $ 511.8 $ 156.5 $ — (1) Included in "Other noncurrent liabilities" in the Consolidated Balance Sheets

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table presents the calculation of our basic and diluted EPS: Year Ended December 31, (in millions, except per share amounts) 2021 2020 2019 Numerator: Net Income (Loss) Available to Common Shareholders - Basic $ 529.8 $ (72.7) $ 328.0 Dilutive effect of Equity Units 1.6 — — Net Income (Loss) Available to Common Shareholders - Diluted $ 531.4 $ (72.7) $ 328.0 Denominator: Average common shares outstanding - Basic 393.6 384.3 374.6 Dilutive potential common shares: Equity Units 22.0 — — Shares contingently issuable under employee stock plans 0.8 — 0.9 Shares restricted under employee stock plans 0.3 — 0.2 ATM Forward agreements 0.6 — 0.3 Average Common Shares - Diluted 417.3 384.3 376.0 Earnings per common share: Basic $ 1.35 $ (0.19) $ 0.88 Diluted $ 1.27 $ (0.19) $ 0.87

Property, Plant And Equipment (

Property, Plant And Equipment (Tables)	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Schedule Of Property, Plant And Equipment	Our property, plant and equipment on the Consolidated Balance Sheets are classified as follows: At December 31, (in millions) 2021 2020 Property, Plant and Equipment Gas Distribution Utility (1) $ 15,240.6 $ 14,010.2 Electric Utility (1) 6,754.9 6,478.0 Corporate 217.8 197.3 Construction Work in Process 808.0 572.6 Renewable Generation Assets (2) 702.4 175.7 Non-Utility and Other (3) 1,447.6 2,746.1 Total Property, Plant and Equipment $ 25,171.3 $ 24,179.9 Accumulated Depreciation and Amortization Gas Distribution Utility (1) $ (3,490.2) $ (3,292.9) Electric Utility (1) (2,433.1) (2,305.0) Corporate (132.2) (109.3) Renewable Generation Assets (2) (6.5) (0.1) Non-Utility and Other (3) (1,227.5) (1,853.1) Total Accumulated Depreciation and Amortization $ (7,289.5) $ (7,560.4) Net Property, Plant and Equipment $ 17,881.8 $ 16,619.5 (1) NIPSCO’s common utility plant and associated accumulated depreciation and amortization are allocated between Gas Distribution Utility and Electric Utility Property, Plant and Equipment. (2) Our renewable generation assets are part of our electric segment and represent Non-Utility Property, owned and operated by joint ventures between NIPSCO and unrelated tax equity partners, and depreciated straight-line over 30 years. Refer to Note 4, "Variable Interest Entities," for additional information. (3) Non-Utility and Other as of December 31, 2020 includes net book value of four coal units totaling $903.8 million related to R.M. Schahfer Generating Station. Two of the four units were subsequently retired in 2021 and reclassified to current and long-term Regulatory Assets. Depreciation expense for the remaining net book value continues to be recorded at the composite depreciation rate approved by the IURC. As of December 31, 2021, Non-Utility and Other includes a net book value of $201.5 million related to the units not yet retired.
Schedule Of Depreciation Provisions For Utility Plant As A Percentage Of The Original Cost	The weighted average depreciation provisions for utility plant, as a percentage of the original cost, for the periods ended December 31, 2021, 2020 and 2019 were as follows: 2021 2020 2019 Electric Operations (1) 3.4 % 3.4 % 2.8 % Gas Distribution Operations 2.2 % 2.3 % 2.5 % (1) Increased rate beginning in 2020 primarily attributable to higher depreciation rates from the recent rate case proceeding.

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2021
Asset Retirement Obligation [Abstract]
Changes In Liability For Asset Retirement Obligations	Changes in our liability for asset retirement obligations for the years 2021 and 2020 are presented in the table below: (in millions) 2021 2020 Beginning Balance $ 495.6 $ 416.9 Accretion recorded as a regulatory asset/liability 16.0 17.3 Additions 23.2 5.5 Settlements (11.2) (13.9) Change in estimated cash flows (11.2) 86.0 (1) Other — (16.2) (2) Ending Balance $ 512.4 $ 495.6 (1) The change in estimated cash flows for 2020 is primarily attributed to revisions to the estimated costs associated with refining the CCR compliance plan, changes in estimated costs for electric generating stations and the changes in estimated costs for retirement of gas mains. See Note 19-E, "Environmental Matters," for additional information on CCRs. (2) Represents the Columbia of Massachusetts Asset Retirement Obligations that were included in the sale of the Massachusetts Business that occurred on October 9, 2020.

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2021
Regulatory Assets and Liabilities Disclosure [Abstract]
Regulatory Assets	Regulatory assets were comprised of the following items: At December 31, (in millions) 2021 2020 Regulatory Assets Unrecognized pension and other postretirement benefit costs (see Note 12) $ 512.1 $ 583.3 Deferred pension and other postretirement benefit costs (see Note 12) 74.8 72.4 Environmental costs (see Note 19-E) 45.8 56.6 Regulatory effects of accounting for income taxes (see Note 1-N and Note 11) 194.8 194.5 Under-recovered gas and fuel costs (see Note 1-J) 73.6 8.0 Depreciation 177.5 192.6 Post-in-service carrying charges 237.9 228.6 Safety activity costs 171.9 146.0 DSM programs 39.2 37.8 Retired coal generating stations 803.9 204.7 Losses on commodity price risk programs (See Note 10) 9.6 54.7 Deferred property taxes 65.1 62.9 Renewable energy investments (See Note 1-S and Note 4) 18.5 — Other 67.5 88.4 Total Regulatory Assets $ 2,492.2 $ 1,930.5 Less: Current Portion 206.2 135.7 Total Noncurrent Regulatory Assets $ 2,286.0 $ 1,794.8
Regulatory Liabilities	Regulatory liabilities were comprised of the following items: At December 31, (in millions) 2021 2020 Regulatory Liabilities Over-recovered gas and fuel costs (see Note 1-J) $ 5.4 $ 47.8 Cost of removal (see Note 8) 749.5 775.2 Regulatory effects of accounting for income taxes (see Note 1-N and Note 11) 1,040.8 1,105.1 Deferred pension and other postretirement benefit costs (see Note 12) 75.9 69.5 Gains on commodity price risk programs (See Note 10) 34.2 14.0 Other 74.2 53.9 Total Regulatory Liabilities $ 1,980.0 $ 2,065.5 Less: Current Portion 137.4 161.3 Total Noncurrent Regulatory Liabilities $ 1,842.6 $ 1,904.2
Schedule of COVID-19 Regulatory Impact	The ongoing impacts of these approvals or directives are described in the table below: Jurisdiction Moratorium in Place? Regulatory Asset balance as of December 31, 2021 (in millions) Regulatory Asset balance as of December 31, 2020 (in millions) Deferred COVID-19 Costs Columbia of Ohio No $ 2.1 $ 2.0 Incremental operation and maintenance expenses NIPSCO No $ 2.2 $ 9.2 Incremental bad debt expense and the costs to implement the requirements of the COVID-19 related order Columbia of Pennsylvania No $ 5.2 $ 5.4 Incremental bad debt expense incurred from March 13, 2020 through December 29, 2021, above levels currently in rates Columbia of Virginia No $ 1.5 $ — Incremental incurred costs (including incremental bad debt expense), subject to an earnings test review Columbia of Maryland No $ 0.9 $ 0.7 Incremental costs (including incremental bad debt expense) incurred to ensure that customers have essential utility service during the state of emergency in Maryland. Such incremental costs must be offset by any benefit received in connection with the pandemic

Risk Management Activities (Tab

Risk Management Activities (Tables)	12 Months Ended
	Dec. 31, 2021
Risk Management Activities [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	Risk management assets and liabilities on our derivatives are presented on the Consolidated Balance Sheets as shown below: December 31, 2021 December 31, 2020 (in millions) Assets Liabilities Assets Liabilities Current (1) Derivatives designated as hedging instruments $ — $ 136.4 $ — $ 70.9 Derivatives not designated as hedging instruments 10.6 0.4 10.4 7.3 Total $ 10.6 $ 136.8 $ 10.4 $ 78.2 Noncurrent (2) Derivatives designated as hedging instruments $ — $ — $ — $ 99.5 Derivatives not designated as hedging instruments 13.8 7.4 2.8 45.1 Total $ 13.8 $ 7.4 $ 2.8 $ 144.6 (1) Presented in "Prepayments and other" and "Other accruals", respectively, on the Consolidated Balance Sheets. (2) Presented in "Deferred charges and other" and "Other noncurrent liabilities", respectively, on the Consolidated Balance Sheets.
Reclassification out of Accumulated Other Comprehensive Income	Cash flow hedges included in Accumulated Other Comprehensive Income (Loss) on the Consolidated Balance Sheets were: (in millions) AOCI (1) Amounts Expected to be Reclassified to Earnings During the Next 12 Months (1) Maximum Term Interest Rate $ 25.4 0.8 371 months (1) All amounts are net of tax.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule Of Components Of Income Tax Expense	The components of income tax expense (benefit) were as follows: Year Ended December 31, (in millions) 2021 2020 2019 Income Taxes Current Federal $ (0.1) $ 0.2 $ — State 6.0 11.7 5.2 Total Current 5.9 11.9 5.2 Deferred Federal 99.2 (0.4) 110.7 State 13.8 (27.4) 9.0 Total Deferred 113.0 (27.8) 119.7 Deferred Investment Credits (1.1) (1.2) (1.4) Income Taxes $ 117.8 $ (17.1) $ 123.5
Schedule Of Reasons Behind Differences In Computation Of Total Income Taxes	The following table represents a reconciliation of income tax expense at the statutory federal income tax rate to the actual income tax expense from continuing operations: Year Ended December 31, (in millions) 2021 2020 2019 Book income (loss) before income taxes $ 706.6 $ (31.3) $ 506.6 Tax expense (benefit) at statutory federal income tax rate 148.3 21.0 % (6.6) 21.0 % 106.5 21.0 % Increases (reductions) in taxes resulting from: State income taxes, net of federal income tax benefit 14.1 2.0 (11.7) 37.4 10.1 2.0 Amortization of regulatory liabilities (39.1) (5.5) (38.4) 122.7 (29.4) (5.8) Goodwill impairment — — — — 43.0 8.5 Fines and penalties — — 11.8 (37.7) 11.5 2.3 Charitable contribution carryover — — — — (2.5) (0.5) State regulatory proceedings — — — — (9.5) (1.9) Employee stock ownership plan dividends and other compensation (1.2) (0.2) (1.3) 4.2 (2.0) (0.4) Deferred taxes on TCJA regulatory liability divested — — 23.3 (74.5) — — Tax accrual adjustments (0.1) — 8.9 (28.4) — — Federal tax credits (2.1) (0.3) (2.5) 8.0 — — Other adjustments (2.1) (0.3) (0.6) 1.9 (4.2) (0.8) Income Taxes $ 117.8 16.7 % $ (17.1) 54.6 % $ 123.5 24.4 %
Schedule Of Principal Components Of Net Deferred Tax Liability	Deferred income taxes result from temporary differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities. The principal components of our net deferred tax liability were as follows: At December 31, (in millions) 2021 2020 Deferred tax liabilities Accelerated depreciation and other property differences $ 2,454.4 $ 2,339.3 Other regulatory assets 308.6 331.8 Total Deferred Tax Liabilities 2,763.0 2,671.1 Deferred tax assets Other regulatory liabilities and deferred investment tax credits (including TCJA) 284.7 287.8 Pension and other postretirement/postemployment benefits 104.8 118.1 Net operating loss carryforward and AMT credit carryforward 545.9 608.5 Environmental liabilities 22.2 22.6 Other accrued liabilities 42.1 41.5 Other, net 111.7 128.4 Total Deferred Tax Assets 1,111.4 1,206.9 Valuation Allowance (7.8) (6.4) Net Deferred Tax Assets 1,103.6 1,200.5 Net Deferred Tax Liabilities $ 1,659.4 $ 1,470.6
Schedule of Unrecognized Tax Benefits Roll Forward	A reconciliation of the beginning and ending amounts of unrecognized tax benefits is as follows: At December 31, 2021, (in millions) 2021 2020 2019 Opening Balance $ 21.7 $ 23.2 $ 1.2 Gross decreases - tax positions in prior period — (1.5) (0.6) Gross increases - current period tax positions — — 22.6 Ending Balance $ 21.7 $ 21.7 $ 23.2 Offset for net operating loss carryforwards (21.7) (21.7) (22.6) Balance, Less Net Operating Loss Carryforwards $ — $ — $ 0.6

Pension and Other Postretirem_2

Pension and Other Postretirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Schedule Of Allocation of Plan Assets	December 31, 2021 Defined Benefit Pension Plan Postretirement Benefit Plan Asset Category Minimum Maximum Minimum Maximum Domestic Equities 7% 27% 0% 55% International Equities 3% 13% 0% 25% Fixed Income 69% 81% 20% 100% Real Estate 0% 3% 0% 0% Private Equity 0% 3% 0% 0% Short-Term Investments 0% 10% 0% 10% December 31, 2020 Defined Benefit Pension Plan Postretirement Benefit Plan Asset Category Minimum Maximum Minimum Maximum Domestic Equities 12% 32% 0% 55% International Equities 6% 16% 0% 25% Fixed Income 59% 71% 20% 100% Real Estate 0% 7% 0% 0% Private Equity 0% 5% 0% 0% Short-Term Investments 0% 10% 0% 10% The actual Pension Plan and Postretirement Plan Asset Mix at December 31, 2021 and December 31, 2020 are as follows: Defined Benefit Pension Assets (1) December 31, Postretirement December 31, Asset Class (in millions) Asset Value % of Total Assets Asset Value % of Total Assets Domestic Equities $ 324.3 16.4 % $ 118.6 40.4 % International Equities 150.9 7.6 % 50.5 17.2 % Fixed Income 1,382.3 69.7 % 118.8 40.4 % Real Estate 37.2 1.9 % — — Cash/Other 87.0 4.4 % 5.8 2.0 % Total $ 1,981.7 100.0 % $ 293.7 100.0 % Defined Benefit Pension Assets (1) December 31, Postretirement Benefit Plan Assets December 31, Asset Class (in millions) Asset Value % of Total Assets Asset Value % of Total Assets Domestic Equities $ 446.3 21.0 % $ 108.8 38.0 % International Equities 230.1 10.9 % 48.2 16.8 % Fixed Income 1,291.2 61.0 % 122.0 42.6 % Real Estate 52.9 2.5 % — — Cash/Other 97.2 4.6 % 7.4 2.6 % Total $ 2,117.7 100.0 % $ 286.4 100.0 % (1) Total includes accrued dividends and pending traders with brokers.
Schedule Of Fair Value and Changes In The Fair Value Of The Plan Assets	Fair Value Measurements at December 31, 2021: (in millions) December 31, Quoted Prices in Active Markets for Significant Other Significant Pension plan assets: Cash $ 10.3 $ 9.7 $ 0.6 $ — Equity securities International equities 0.5 0.5 — — Fixed income securities Government 387.3 — 387.3 — Corporate 645.9 — 645.9 — Mutual Funds U.S. multi-strategy 128.4 128.4 — — International equities 38.7 38.7 — — Private equity limited partnerships (3) U.S. multi-strategy (1) 10.9 — — — International multi-strategy (2) 4.5 — — — Distressed opportunities 0.1 — — — Real estate (3) 37.2 — — — Commingled funds (3) Short-term money markets 55.0 — — — U.S. equities 195.9 — — — International equities 111.7 — — — Fixed income 349.1 — — — Pension plan assets subtotal 1,975.5 177.3 1,033.8 — Other postretirement benefit plan assets: Mutual funds U.S. multi-strategy 103.8 103.8 — — International equities 24.4 24.4 — — Fixed income 118.5 118.5 — — Commingled funds (3) Short-term money markets 5.8 — — — U.S. equities 14.8 — — — International equities 26.1 — — — Other postretirement benefit plan assets subtotal 293.4 246.7 — — Due to brokers, net (4) (1.8) — (1.8) — Receivables/payables 0.3 — 0.3 — Accrued income/dividends 8.0 8.0 — — Total pension and other postretirement benefit plan assets $ 2,275.4 $ 432.0 $ 1,032.3 $ — (1) This class includes limited partnerships/fund of funds that invest in a diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily inside the United States. (2) This class includes limited partnerships/fund of funds that invest a in diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily outside the United States. (3) This class of investments is measured at fair value using the net asset value per share and has not been classified in the fair value hierarchy. (4) This class represents pending trades with brokers. The table below sets forth a summary of unfunded commitments, redemption frequency and redemption notice periods for certain investments that are measured at fair value using the net asset value per share for the year ended December 31, 2021: (in millions) Fair Value Unfunded Commitments Redemption Frequency Redemption Notice Period Commingled Funds Short-term money markets $ 60.8 $ — Daily 1 day U.S. equities 210.7 — Daily 1 day - 5 days International equities 137.8 — Monthly 10 days-30 days Fixed income 349.1 — Daily 3 days Private Equity and Real Estate Limited Partnerships (1) 20.4 12.1 N/A N/A Total $ 778.8 $ 12.1 (1) Private equity and real estate limited partnerships typically call capital over a 3-5 year period and pay out distributions as the underlying investments are liquidated. The typical expected life of these limited partnerships is 0-15 years, and these investments typically cannot be redeemed prior to liquidation. Fair Value Measurements at December 31, 2020: (in millions) December 31, Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Significant Pension plan assets: Cash $ 11.9 $ 11.9 $ — $ — Equity securities U.S. equities 2.4 2.4 — — Fixed income securities Government 243.4 — 243.4 — Corporate 692.6 — 692.6 — Mutual Funds U.S. multi-strategy 161.3 161.3 — — International equities 55.4 55.4 — — Fixed income 0.1 0.1 — — Private equity limited partnerships (3) U.S. multi-strategy (1) 10.9 — — — International multi-strategy (2) 6.6 — — — Distressed opportunities 0.3 — — — Real Estate 52.9 — — — Commingled funds (3) Short-term money markets 78.8 — — — U.S. equities 279.7 — — — International equities 176.8 — — — Fixed income 337.6 — — — Pension plan assets subtotal 2,110.7 231.1 936.0 — Other postretirement benefit plan assets: Mutual funds U.S. multi-strategy 94.8 94.8 — — International equities 24.1 24.1 — — Fixed income 121.8 121.8 — — Commingled funds (3) Short-term money markets 7.6 — — — U.S. equities 14.0 — — — International equities 24.1 — — — Other postretirement benefit plan assets subtotal 286.4 240.7 — — Due to brokers, net (4) (1.6) — (1.6) — Accrued income/dividends 8.6 8.6 — — Total pension and other postretirement benefit plan assets $ 2,404.1 $ 480.4 $ 934.4 $ — (1) This class includes limited partnerships/fund of funds that invest in a diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily inside the United States. (2) This class includes limited partnerships/fund of funds that invest in diverse portfolio of private equity strategies, including buy-outs, venture capital, growth capital, special situations and secondary markets, primarily outside the United States. (3) This class of investments is measured at fair value using the net asset value per share and has not been classified in the fair value hierarchy. (4) This class represents pending trades with brokers. The table below sets forth a summary of unfunded commitments, redemption frequency and redemption notice periods for certain investments that are measured at fair value using the net asset value per share for the year ended December 31, 2020: (in millions) Fair Value Unfunded Commitments Redemption Frequency Redemption Notice Period Commingled Funds Short-term money markets $ 86.4 $ — Daily 1 day U.S. equities 293.7 — Monthly 1 day -5 days International equities 200.9 — Monthly 10 days - 30 days Fixed income 337.6 — Daily 3 days Private Equity and Real Estate Limited Partnerships (1) 22.7 12.1 N/A N/A Total $ 941.3 $ 12.1 (1) Private equity and real estate limited partnerships typically call capital over a 3-5 year period and pay out distributions as the underlying investments are liquidated. The typical expected life of these limited partnerships is 0-15 years, and these investments typically cannot be redeemed prior to liquidation.
Schedule Of Reconciliation Of The Plan Funded Status	The following table provides a reconciliation of the plans’ funded status and amounts reflected in our Consolidated Balance Sheets at December 31 based on a December 31 measurement date: Pension Benefits Other Postretirement Benefits (in millions) 2021 2020 2021 2020 Change in projected benefit obligation (1) Benefit obligation at beginning of year $ 2,058.4 $ 2,130.5 $ 590.8 $ 576.5 Service cost 30.2 32.0 6.2 6.6 Interest cost 31.4 51.6 9.9 15.4 Plan participants’ contributions — — 4.2 4.1 Plan amendments — — 0.1 — Actuarial (gain) loss (2) (68.7) 140.1 (14.8) 24.8 Benefits paid (198.9) (174.5) (40.6) (37.0) Estimated benefits paid by incurred subsidy — — 0.4 0.4 Spinoff to Eversource — (121.3) — — Projected benefit obligation at end of year $ 1,852.4 $ 2,058.4 $ 556.2 $ 590.8 Change in plan assets Fair value of plan assets at beginning of year $ 2,117.7 $ 2,080.9 $ 286.4 $ 261.4 Actual return on plan assets 58.9 329.9 23.9 36.3 Employer contributions 4.0 2.9 19.8 21.6 Plan participants’ contributions — — 4.2 4.1 Benefits paid (198.9) (174.6) (40.6) (37.0) Spinoff to Eversource — (121.4) — — Fair value of plan assets at end of year $ 1,981.7 $ 2,117.7 $ 293.7 $ 286.4 Funded Status at end of year $ 129.3 $ 59.3 $ (262.5) $ (304.4) Amounts recognized in the statement of financial position consist of: Noncurrent assets 159.3 91.4 — — Current liabilities (2.8) (2.9) (1.0) (0.9) Noncurrent liabilities (27.2) (29.2) (261.5) (303.5) Net amount recognized at end of year (3) $ 129.3 $ 59.3 $ (262.5) $ (304.4) Amounts recognized in accumulated other comprehensive income or regulatory asset/liability (4) Unrecognized prior service credit $ 0.3 $ 0.3 $ (7.8) $ (10.1) Unrecognized actuarial loss 438.0 497.2 88.5 116.4 Net amount recognized at end of year $ 438.3 $ 497.5 $ 80.7 $ 106.3 (1) The change in benefit obligation for Pension Benefits represents the change in Projected Benefit Obligation while the change in benefit obligation for Other Postretirement Benefits represents the change in accumulated postretirement benefit obligation. (2) The pension actuarial gain was primarily driven by the increase in discount rate. The postretirement benefit gain was also primarily driven by an increase in discount rates. (3) We recognize our Consolidated Balance Sheets underfunded and overfunded status of our various defined benefit postretirement plans, measured as the difference between the fair value of the plan assets and the benefit obligation. (4) We determined that for certain rate-regulated subsidiaries the future recovery of pension and other postretirement benefits costs is probable. These rate-regulated subsidiaries recorded regulatory assets and liabilities of $512.1 million and zero, respectively, as of December 31, 2021, and $583.3 million and zero, respectively, as of December 31, 2020 that would otherwise have been recorded to accumulated other comprehensive loss.
Schedule of Benefit Obligations in Excess of Fair Value of Plan Assets	Information for pension plans with a projected benefit obligation in excess of plan assets: December 31, 2021 2020 Accumulated Benefit Obligation $ 30.0 $ 32.1 Funded Status Projected Benefit Obligation 30.0 32.1 Fair Value of Plan Assets — — Funded Status of Underfunded Pension Plans at End of Year (1) $ (30.0) $ (32.1) (1) As of December 31, 2021 and 2020, only our nonqualified plans were underfunded. These plans have no assets as they are not funded until benefits are paid. Information for pension plans with plan assets in excess of the projected benefit obligation: December 31, 2021 2020 Accumulated Benefit Obligation $ 1,804.3 $ 2,004.7 Funded Status Projected Benefit Obligation 1,822.4 2,026.3 Fair Value of Plan Assets 1,981.7 2,117.7 Funded Status of Overfunded Pension Plans at End of Year $ 159.3 $ 91.4
Schedule Of Expected Payments To Participants In Pension Plan	The expected benefits are estimated based on the same assumptions used to measure our benefit obligation at the end of the year and include benefits attributable to the estimated future service of employees: (in millions) Pension Benefits Other Federal Year(s) 2022 $ 157.3 $ 38.1 $ 0.4 2023 150.4 37.4 0.4 2024 145.6 36.9 0.3 2025 143.1 36.5 0.3 2026 135.7 35.8 0.3 2027-2031 598.9 168.7 1.1
Components Of The Plans' Net Periodic Benefits Cost	The following table provides the components of the plans’ actuarially determined net periodic benefits cost for each of the three years ended December 31, 2021, 2020 and 2019: Pension Benefits Other Postretirement (in millions) 2021 2020 2019 2021 2020 2019 Components of Net Periodic Benefit (Income) Cost (1) Service cost $ 30.2 $ 32.0 $ 29.2 $ 6.2 $ 6.6 $ 5.1 Interest cost 31.4 51.6 72.3 9.9 15.4 19.2 Expected return on assets (101.6) (111.6) (108.8) (15.3) (14.4) (13.1) Amortization of prior service cost (credit) 0.1 0.7 0.2 (2.2) (2.1) (3.2) Recognized actuarial loss 21.7 33.8 45.2 4.6 4.9 2.0 Settlement/curtailment loss 11.4 10.5 9.5 — 1.5 — Total Net Periodic Benefits (Income) Cost $ (6.8) $ 17.0 $ 47.6 $ 3.2 $ 11.9 $ 10.0 (1) Service cost is presented in "Operation and maintenance" on the Statements of Consolidated Income (Loss). Non-service cost components are presented within "Other, net."
Schedule Of Significant Actuarial Assumptions In Determining Funded Status Plan	The following table provides the key assumptions that were used to calculate the pension and other postretirement benefits obligations for our various plans as of December 31: Pension Benefits Other Postretirement Benefits 2021 2020 2021 2020 Weighted-average assumptions to Determine Benefit Obligation Discount Rate 2.76 % 2.38 % 2.85 % 2.49 % Rate of Compensation Increases 4.00 % 4.00 % — — Interest Crediting Rates 4.00 % 4.00 % — — Health Care Trend Rates Trend for Next Year — — 6.20 % 6.69 % Ultimate Trend — — 4.50 % 4.50 % Year Ultimate Trend Reached — — 2030 2029 The following table provides the key assumptions that were used to calculate the net periodic benefits cost for our various plans: Pension Benefits Other Postretirement 2021 2020 2019 2021 2020 2019 Weighted-average Assumptions to Determine Net Periodic Benefit Cost Discount rate - service cost 2.81 % 3.39 % 4.48 % 3.00 % 3.52 % 4.59 % Discount rate - interest cost 1.57 % 2.65 % 3.84 % 1.73 % 2.76 % 3.94 % Expected Long-Term Rate of Return on Plan Assets 5.20 % 5.70 % 6.10 % 5.50 % 5.67 % 5.83 % Rate of Compensation Increases 4.00 % 4.00 % 4.00 % — — — Interest Crediting Rates 4.00 % 4.00 % 4.00 % — — —
Schedule Of Changes In Plan Assets And Projected Benefit Obligations Recognized In Other Comprehensive Income	The following table provides other changes in plan assets and projected benefit obligations recognized in other comprehensive income or regulatory asset or liability: Pension Benefits Other Postretirement (in millions) 2021 2020 2021 2020 Other Changes in Plan Assets and Projected Benefit Obligations Net prior service cost $ — $ — $ 0.1 $ — Net actuarial loss (gain) (26.0) (78.2) (23.3) 2.9 Settlements/curtailments (11.4) (10.5) — (1.5) Less: amortization of prior service cost (0.1) (0.7) 2.2 2.1 Less: amortization of net actuarial loss (21.7) (33.8) (4.6) (4.9) Less: gain attributable to spinoff to Eversource — (33.1) — — Less: prior service cost attributable to spinoff to Eversource — (2.0) — — Total Recognized in Other Comprehensive Income or Regulatory $ (59.2) $ (158.3) $ (25.6) $ (1.4) Amount Recognized in Net Periodic Benefits Cost and Other $ (66.0) $ (141.3) $ (22.4) $ 10.5

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Schedule Of Stock Offering Program	The following table summarizes our activity under the ATM program. Year Ending December 31, 2021 2020 2019 Number of shares issued 12,525,215 8,459,430 8,422,498 Average price per share $ 23.95 $ 23.60 $ 27.75 Proceeds, net of fees ( in millions) $ 288.1 $ 196.5 $ 229.1
Schedule of Stock by Class - Preferred	The following table summarizes preferred stock by outstanding series of shares: Year ended December 31, December 31, December 31, 2021 2020 2019 2021 2020 (in millions except shares and per share amounts) Liquidation Preference Per Share Shares Dividends Declared Per Share Outstanding 5.650% Series A $ 1,000.00 400,000 $ 56.50 $ 56.50 $ 56.50 $ 393.9 $ 393.9 6.500% Series B $ 25,000.00 20,000 $ 1,625.00 $ 1,625.00 $ 1,674.65 $ 486.1 $ 486.1 Series C (1) $ 1,000.00 862,500 — — — $ 666.5 $ — (1) The Series C Mandatory Convertible Preferred Stock initially will not bear any dividends. We recorded the initial present value of the purchase contract payments as a liability with a corresponding reduction to preferred stock. Equity Units. On April 19, 2021, we completed the sale of 8.625 million Equity Units, initially consisting of Corporate Units, each with a stated amount of $100. The offering generated net proceeds of $835.5 million, after underwriting and issuance expenses. Each Corporate Unit consists of a forward contract to purchase shares of our common stock in the future and a 1/10th, or 10%, undivided beneficial ownership interest in one share of Series C Mandatory Convertible Preferred Stock, par value $0.01 per share, with a liquidation preference of $1,000 per share. The purchase contract obligates holders to purchase shares of our common stock on December 1, 2023, subject to early settlement in certain situations. The purchase price paid under the purchase contract is $100 and the number of shares to be purchased will be determined under a settlement rate formula based on the volume-weighted average share price of our common stock near the settlement date, subject to a maximum settlement rate. The Series C Mandatory Convertible Preferred Stock will initially be pledged upon issuance as collateral to secure the purchase of common stock under the related purchase contracts. We will pay quarterly contract adjustment payments at the rate of 7.75% per year on the stated amount of $100 per Equity Unit. The contract adjustment payments are payable in cash, shares of our common stock or a combination thereof, at our election. We have the right to defer the payment of contract adjustment payments until no later than the purchase contract settlement date. If we exercise our option to defer the payment of contract adjustment payments, then until the deferred contract adjustment payments have been paid, we will not declare or pay any dividends on, or make any distributions on, or redeem, purchase or acquire, or make a liquidation payment with respect to, any shares of our capital stock; make any payment of principal of, or interest or premium, if any, on, or repay, repurchase or redeem any of our debt securities that rank on parity with, or junior to, the contract adjustment payments; or make any guarantee payments under any guarantee by us of securities of any of our subsidiaries if our guarantee ranks on parity with, or junior to, the contract adjustment payments. The Series C Mandatory Convertible Preferred Stock initially will not bear any dividends and the liquidation preference of the mandatory convertible preferred stock will not accrete. The Series C Mandatory Convertible Preferred Stock is expected to be remarketed prior to December 1, 2023. Following a successful remarketing, dividends may become payable on the Series C Mandatory Convertible Preferred Stock and/or the minimum conversion rate of the Series C Mandatory Convertible Preferred Stock may be increased. Each share of Series C Mandatory Convertible Preferred Stock, unless previously converted, will automatically convert based on a conversion rate on the mandatory conversion date, which is expected to be on or about March 1, 2024. The conversion rate will be determined based on the volume-weighted average share price of our common stock near the conversion date, subject to a minimum and maximum conversion rate. If no successful remarketing of the Series C Mandatory Convertible Preferred Stock has previously occurred, effective as of December 1, 2023, the conversion rate will be zero, no shares of our common stock will be delivered upon automatic conversion and each share of Series C Mandatory Convertible Preferred Stock will be automatically transferred to us on the mandatory conversion date without any payment of cash or shares of our common stock thereon. In the event of such a remarketing failure, any shares of Series C Mandatory Convertible Preferred Stock held as part of Corporate Units will be automatically delivered to us on December 1, 2023 in full satisfaction of the relevant holder's obligation under the related purchase contracts. The Series C Mandatory Convertible Preferred Stock and forward purchase contracts are legally detachable and separately exercisable, however, due to the economic linkage between the forward purchase contract and the Series C Mandatory Convertible Preferred Stock, we have concluded that the ability to separate the Corporate Units is non-substantive. Accordingly, we are accounting for the Corporate Units as a single unit of account. We recorded the initial present value of the purchase contract payments as a liability with a corresponding reduction to preferred stock. The current portion of this liability is included in "Other accruals," and the noncurrent portion is included in "Other noncurrent liabilities" on the Consolidated Balance Sheets. Purchase contract payments are recorded against this liability. Accretion of the stock purchase contract liability is recorded as interest expense. Refer to Note 5, "Earnings Per Share," for additional information regarding our application of diluted EPS to the shares underlying purchase contracts and the Series C Mandatory Convertible Preferred Stock as part of the Equity Units. Under the terms of the Equity Units, assuming no anti-dilution or other adjustments such as a fundamental change, the maximum number of shares of common stock we will issue under the purchase contracts is 35.2 million and maximum number of shares of common stock we will issue under the Series C Mandatory Convertible Preferred Stock is 35.2 million. Selected information about the Equity Units is presented below: (in millions except contract rate) Issuance Date Units Issued Total Net Proceeds (1) Purchase Contract Annual Rate Purchase Contract Liability (2) Equity Units April 19, 2021 8.625 $ 835.5 7.75 % $ 168.8 (1) Issuance costs of $27.0 million were recorded on a relative fair value basis as a reduction to preferred stock of $22.5 million and a reduction to the purchase contract liability of $4.5 million. (2) Cash payments of $41.2 million and zero were made during the years ended December 31, 2021 and December 31, 2020, respectively. The purchase contract liability was $129.4 million at December 31, 2021. Noncontrolling Interest in Consolidated Subsidiaries. As of December 31, 2021 and 2020, NIPSCO and tax equity partners have completed their cash contributions into the Indiana Crossroads Wind and Rosewater joint ventures. Earnings, tax attributes and cash flows are allocated to both NIPSCO and the respective tax equity partners in varying percentages by category and over the life of the partnership. The tax equity partner's contributions, net of these allocations, is represented as a noncontrolling interest within total equity on the Consolidated Balance Sheets. Refer to Note 4, "Variable Interest Entities," for more information.
Equity Units	Selected information about the Equity Units is presented below: (in millions except contract rate) Issuance Date Units Issued Total Net Proceeds (1) Purchase Contract Annual Rate Purchase Contract Liability (2) Equity Units April 19, 2021 8.625 $ 835.5 7.75 % $ 168.8 (1) Issuance costs of $27.0 million were recorded on a relative fair value basis as a reduction to preferred stock of $22.5 million and a reduction to the purchase contract liability of $4.5 million. (2) Cash payments of $41.2 million and zero were made during the years ended December 31, 2021 and December 31, 2020, respectively. The purchase contract liability was $129.4 million at December 31, 2021.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement, Noncash Expense [Abstract]
Performance Award Details	The following table presents details of the performance awards described above. Award Year Service Conditions Lapse date Performance Period Award Conditions Shares outstanding at 12/31/2021 (shares) Grant Date Fair Value (in millions) 2021 02/28/24 01/01/2021- Non-GAAP Financial Measure 278,328 $ 6.5 Relative Total Shareholder Return 278,328 $ 6.7 Relative Total Shareholder Return 124,200 $ 3.2 02/28/23 01/01/2021- 12/31/2022 Relative Total Shareholder Return 252,082 $ 4.8 2020 02/28/23 01/01/2020- Non-GAAP Financial Measure 349,686 $ 11.7 Operational Measures 80,696 $ 2.6 2019 02/28/22 01/01/2019- Non-GAAP Financial Measure 353,302 $ 11.7 Operational Measures 81,528 $ 2.5
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule Of Transactions Of Share Based Compensation Other Than Stock Options	(shares) Restricted Stock Weighted Average Non-vested at December 31, 2020 478,227 24.51 Granted 285,755 19.83 Forfeited (36,697) 23.72 Vested (155,131) 22.66 Non-vested at December 31, 2021 572,154 22.72
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule Of Transactions Of Share Based Compensation Other Than Stock Options	(shares) Performance Weighted Average Non-vested at December 31, 2020 1,384,336 25.09 Granted 973,885 21.76 Forfeited (133,695) 25.25 Vested (426,375) 22.09 Non-vested at December 31, 2021 1,798,151 23.78

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2021
Long-term Debt, Current and Noncurrent [Abstract]
Schedule of Long-Term Debt	Our long-term debt as of December 31, 2021 and 2020 is as follows: Long-term debt type Maturity as of December 31, 2021 Weighted average interest rate (%) Outstanding balance as of December 31, (in millions) 2021 2020 Senior notes: NiSource August 2025 0.95 % 1,250.0 1,250.0 NiSource May 2027 3.49 % 1,000.0 1,000.0 NiSource December 2027 6.78 % 3.0 3.0 NiSource September 2029 2.95 % 750.0 750.0 NiSource May 2030 3.60 % 1,000.0 1,000.0 NiSource February 2031 1.70 % 750.0 750.0 NiSource December 2040 6.25 % 152.6 152.6 NiSource June 2041 5.95 % 347.4 347.4 NiSource February 2042 5.80 % 250.0 250.0 NiSource February 2043 5.25 % 500.0 500.0 NiSource February 2044 4.80 % 750.0 750.0 NiSource February 2045 5.65 % 500.0 500.0 NiSource May 2047 4.38 % 1,000.0 1,000.0 NiSource March 2048 3.95 % 750.0 750.0 Total senior notes $ 9,003.0 $ 9,003.0 Medium term notes: NiSource April 2022 to May 2027 7.99 % $ 49.0 $ 49.0 NIPSCO August 2022 to August 2027 7.61 % 68.0 68.0 Columbia of Massachusetts December 2025 to February 2028 6.37 % 15.0 15.0 Total medium term notes $ 132.0 $ 132.0 Finance leases: NiSource Corporate Services March 2022 to December 2025 1.73 % 51.4 49.4 NIPSCO December 2027 to January 2033 1.86 % 18.7 16.0 Columbia of Ohio December 2025 to March 2044 6.15 % 87.8 91.2 Columbia of Virginia July 2029 to November 2039 6.28 % 17.7 18.4 Columbia of Kentucky May 2027 3.79 % 0.2 0.3 Columbia of Pennsylvania August 2027 to May 2035 6.35 % 9.8 19.7 Total finance leases 185.6 195.0 Unamortized issuance costs and discounts $ (79.1) $ (86.9) Total Long-Term Debt $ 9,241.5 $ 9,243.1

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Lease Cost	Income statement presentation for these costs (when ultimately recognized on the income statement) is also included: Year Ended December 31, (in millions) Income Statement Classification 2021 2020 Finance lease cost Amortization of right-of-use assets Depreciation and amortization $ 28.8 $ 23.4 Interest on lease liabilities Interest expense, net 9.4 11.1 Total finance lease cost 38.2 34.5 Operating lease cost Operation and maintenance 15.6 20.3 Total lease cost $ 53.8 $ 54.8
Right-of-Use Assets and Liabilities	Our right-of-use assets and liabilities are presented in the following lines on the Consolidated Balance Sheets: At December 31, (in millions) Balance Sheet Classification 2021 2020 Assets Finance leases Net Property, Plant and Equipment $ 165.7 $ 176.8 Operating leases Deferred charges and other 33.8 39.9 Total leased assets 199.5 216.7 Liabilities Current Finance leases Current portion of long-term debt 28.1 23.3 Operating leases Other accruals 6.7 10.3 Noncurrent Finance leases Long-term debt, excluding amounts due within one year 157.5 171.7 Operating leases Other noncurrent liabilities 27.9 29.9 Total lease liabilities $ 220.2 $ 235.2
Lease Information	Other pertinent information related to leases was as follows: Year Ended December 31, (in millions) 2021 2020 Cash paid for amounts included in the measurement of lease liabilities Operating cash flows used for finance leases $ 9.4 $ 11.1 Operating cash flows used for operating leases 15.4 20.2 Financing cash flows used for finance leases 25.7 18.4 Right-of-use assets obtained in exchange for lease obligations Finance leases 22.4 59.3 Operating leases $ 6.0 $ 10.9 December 31, 2021 December 31, 2020 Weighted-average remaining lease term (years) Finance leases 10.6 11.2 Operating leases 8.5 8.0 Weighted-average discount rate Finance leases 5.0 % 5.1 % Operating leases 3.7 % 4.0 %
Lease Maturity	Maturities of our lease liabilities as of December 31, 2021 were as follows: As of December 31, 2021, (in millions) Total Finance Leases Operating Leases 2022 $ 45.1 $ 37.2 $ 7.9 2023 38.5 33.6 4.9 2024 30.2 25.6 4.6 2025 23.2 19.2 4.0 2026 19.6 15.8 3.8 Thereafter 129.1 112.9 16.2 Total lease payments 285.7 244.3 41.4 Less: Imputed interest (65.5) (58.7) (6.8) Total 220.2 185.6 34.6 Reported as of December 31, 2021 Short-term lease liabilities 34.8 28.1 6.7 Long-term lease liabilities 185.4 157.5 27.9 Total lease liabilities $ 220.2 $ 185.6 $ 34.6

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables present financial assets and liabilities measured and recorded at fair value on our Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2021 and December 31, 2020: Recurring Fair Value Measurements December 31, 2021 ( in millions ) Quoted Prices Significant Other Significant Balance as of December 31, 2021 Assets Risk management assets $ — $ 24.4 $ — $ 24.4 Available-for-sale debt securities — 171.8 — 171.8 Total $ — $ 196.2 $ — $ 196.2 Liabilities Risk management liabilities $ — $ 144.2 $ — $ 144.2 Total $ — $ 144.2 $ — $ 144.2 Recurring Fair Value Measurements December 31, 2020 ( in millions ) Quoted Prices Significant Other Significant Balance as of December 31, 2020 Assets Risk management assets $ — $ 13.2 $ — $ 13.2 Available-for-sale debt securities — 170.9 — 170.9 Total $ — $ 184.1 $ — $ 184.1 Liabilities Risk management liabilities $ — $ 222.8 $ — $ 222.8 Total $ — $ 222.8 $ — $ 222.8
Debt Securities, Available-for-sale	The amortized cost, gross unrealized gains and losses, allowance for credit losses, and fair value of available-for-sale securities at December 31, 2021 and 2020 were: December 31, 2021 (in millions) Amortized Gross Gross Unrealized Losses (1) Allowance for Credit Losses Fair Value Available-for-sale debt securities U.S. Treasury debt securities $ 52.8 $ 0.1 $ (0.4) $ — $ 52.5 Corporate/Other debt securities 116.5 3.7 (0.7) (0.2) 119.3 Total $ 169.3 $ 3.8 $ (1.1) $ (0.2) $ 171.8 December 31, 2020 (in millions) Amortized Gross Gross Unrealized Losses (2) Allowance for Credit Losses Fair Value Available-for-sale debt securities U.S. Treasury debt securities $ 33.7 $ 0.3 $ — $ — $ 34.0 Corporate/Other debt securities 130.2 7.7 (0.5) (0.5) 136.9 Total $ 163.9 $ 8.0 $ (0.5) $ (0.5) $ 170.9 (1) Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $36.2 and $35.4 million, respectively, at December 31, 2021. (2) Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is zero and $13.2 million, respectively, at December 31, 2020.
Carrying Amount And Estimated Fair Values Of Financial Instruments	The carrying amount and estimated fair values of these financial instruments were as follows: At December 31, (in millions) Carrying Amount 2021 Estimated Fair Value 2021 Carrying Amount 2020 Estimated Fair Value 2020 Long-term debt (including current portion) $ 9,241.5 $ 10,415.7 $ 9,243.1 $ 11,034.2

Other Commitments And Conting_2

Other Commitments And Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Contractual Obligation, Fiscal Year Maturity	Contractual Obligations. We have certain contractual obligations requiring payments at specified periods. The obligations include long-term debt, lease obligations, energy commodity contracts and obligations for various services including pipeline capacity and outsourcing of IT services. The total contractual obligations in existence at December 31, 2021 and their maturities were: (in millions) Total 2022 2023 2024 2025 2026 After Long-term debt (1) $ 9,135.0 $ 30.0 $ — $ — $ 1,260.0 $ — $ 7,845.0 Interest payments on long-term debt 5,710.0 335.7 334.1 334.1 334.1 321.6 4,050.4 Finance leases (2) 244.3 37.2 33.6 25.6 19.2 15.8 112.9 Operating leases (3) 41.4 7.9 4.9 4.6 4.0 3.8 16.2 Energy commodity contracts 68.6 60.4 8.2 — — — — Service obligations: Pipeline service obligations 1,605.0 610.5 366.0 241.0 136.1 98.7 152.7 IT service obligations 180.1 69.5 44.8 35.7 27.6 2.5 — Other liabilities (4) 553.0 95.6 457.4 — — — — Total contractual obligations $ 17,537.4 $ 1,246.8 $ 1,249.0 $ 641.0 $ 1,781.0 $ 442.4 $ 12,177.2 (1) Long-term debt balance excludes unamortized issuance costs and discounts of $79.1 million. (2) Finance lease payments shown above are inclusive of interest totaling $58.7 million. (3) Operating lease payments shown above are inclusive of interest totaling $6.8 million. Operating lease balances do not include obligations for possible fleet vehicle lease renewals beyond the initial lease term. While we have the ability to renew these leases beyond the initial term, we are not reasonably certain to do so as they are renewed month-to-month after the first year. If we were to continue the fleet vehicle leases outstanding at December 31, 2021, payments would be $33.3 million in 2022, $30.2 million in 2023, $27.2 million in 2024, $24.0 million in 2025, $17.0 million in 2026 and $16.1 million thereafter. (4) Other liabilities shown above are inclusive of the Rosewater and Indiana Crossroads Developer payments due in 2023 and Equity Unit purchase contract liability payments to be made in 2022 and 2023.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2021
Components of Accumulated Other Comprehensive Income (Loss) [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table displays the activity of Accumulated Other Comprehensive Loss, net of tax: (in millions) Gains and Losses on Securities (1) Gains and Losses on Cash Flow Hedges (1) Pension and OPEB Items (1) Accumulated Other Comprehensive Loss (1) Balance as of January 1, 2019 $ (2.4) $ (13.0) $ (21.8) $ (37.2) Other comprehensive income (loss) before reclassifications 6.1 (64.3) 2.3 (55.9) Amounts reclassified from accumulated other comprehensive loss (0.4) 0.1 0.8 0.5 Net current-period other comprehensive income (loss) 5.7 (64.2) 3.1 (55.4) Balance as of December 31, 2019 $ 3.3 $ (77.2) $ (18.7) $ (92.6) Other comprehensive income (loss) before reclassifications 3.3 (70.8) 2.9 (64.6) Amounts reclassified from accumulated other comprehensive loss (0.6) 0.1 1.0 0.5 Net current-period other comprehensive income (loss) 2.7 (70.7) 3.9 (64.1) Balance as of December 31, 2020 $ 6.0 $ (147.9) $ (14.8) $ (156.7) Other comprehensive income (loss) before reclassifications (3.5) 25.3 6.6 28.4 Amounts reclassified from accumulated other comprehensive loss (0.4) 0.1 1.8 1.5 Net current-period other comprehensive income (loss) (3.9) 25.4 8.4 29.9 Balance as of December 31, 2021 $ 2.1 $ (122.5) $ (6.4) $ (126.8) (1) All amounts are net of tax. Amounts in parentheses indicate debits.

Other, Net (Tables)

Other, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Other Nonoperating Income (Expense) [Abstract]
Schedule Of Other, Net	Year Ended December 31, (in millions) 2021 2020 2019 Interest income $ 4.0 $ 5.5 $ 7.7 AFUDC equity 13.1 9.9 8.0 Charitable contributions (11.5) (1.5) (5.1) Pension and other postretirement non-service cost (1) 35.5 9.3 (16.5) Sale of emission reduction credits — 4.6 — Miscellaneous (0.3) 4.3 0.7 Total Other, net $ 40.8 $ 32.1 $ (5.2) (1) See Note 12, "Pension and Other Postretirement Benefits" for additional information.

Interest Expense, Net (Tables)

Interest Expense, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Interest Expense [Abstract]
Schedule Of Interest Expense, Net	Year Ended December 31, (in millions) 2021 2020 2019 Interest on long-term debt $ 336.4 $ 354.2 $ 327.7 Interest on short-term borrowings 0.6 14.7 50.8 Debt discount/cost amortization 11.0 9.1 8.3 Accounts receivable securitization fees 1.4 2.6 2.6 Allowance for borrowed funds used and interest capitalized during construction (4.6) (7.0) (7.5) Debt-based post-in-service carrying charges (14.7) (14.6) (18.7) Other 11.0 11.7 15.7 Total Interest Expense, net $ 341.1 $ 370.7 $ 378.9

Segments Of Business (Tables)

Segments Of Business (Tables)	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Schedule Of Operating Income Derived From Revenues And Expenses By Segment	Year Ended December 31, (in millions) 2021 2020 2019 Operating Revenues Gas Distribution Operations Unaffiliated $ 3,171.2 $ 3,128.1 $ 3,509.7 Intersegment 12.3 12.1 13.1 Total 3,183.5 3,140.2 3,522.8 Electric Operations Unaffiliated 1,696.3 1,535.9 1,698.4 Intersegment 0.8 0.7 0.8 Total 1,697.1 1,536.6 1,699.2 Corporate and Other Unaffiliated 32.1 17.7 0.8 Intersegment 460.3 449.8 468.1 Total 492.4 467.5 468.9 Eliminations (473.4) (462.6) (482.0) Consolidated Operating Revenues $ 4,899.6 $ 4,681.7 $ 5,208.9 Year Ended December 31, (in millions) 2021 2020 2019 Operating Income (Loss) Gas Distribution Operations (1) $ 617.5 $ 199.1 $ 675.4 Electric Operations 387.8 348.8 406.8 Corporate and Other (2) 1.6 2.9 (191.5) Consolidated Operating Income $ 1,006.9 $ 550.8 $ 890.7 Depreciation and Amortization Gas Distribution Operations $ 383.0 $ 363.1 $ 403.2 Electric Operations 329.4 321.3 277.3 Corporate and Other 36.0 41.5 36.9 Consolidated Depreciation and Amortization $ 748.4 $ 725.9 $ 717.4 Assets Gas Distribution Operations $ 15,153.7 $ 13,433.0 $ 14,224.5 Electric Operations 7,178.9 6,443.1 6,027.6 Corporate and Other 1,824.3 2,164.4 2,407.7 Consolidated Assets $ 24,156.9 $ 22,040.5 $ 22,659.8 Capital Expenditures (3) Gas Distribution Operations $ 1,406.4 $ 1,266.9 $ 1,380.3 Electric Operations 517.4 422.8 468.9 Corporate and Other 16.6 31.1 18.6 Consolidated Capital Expenditures $ 1,940.4 $ 1,720.8 $ 1,867.8 (1) In 2020, Gas Distribution Operations reflects the loss of $412.4 million on the sale of the Massachusetts Business. (2) In 2019, Corporate and Other reflects an impairment charge of $204.8 million for goodwill related to Columbia of Massachusetts. For additional information, see Note 7, "Goodwill and Other Intangible Assets." (3) Amounts differ from those presented on the Statements of Consolidated Cash Flows primarily due to the inclusion of capital expenditures in current liabilities, the capitalized portion of the Corporate Incentive Plan payout, and AFUDC Equity.

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2021
Supplemental Cash Flow Information [Abstract]
Schedule of Cash Flow, Supplemental Disclosures	The following table provides additional information regarding our Consolidated Statements of Cash Flows for the years ended December 31, 2021, 2020 and 2019: Year Ended December 31, (in millions) 2021 2020 2019 Supplemental Disclosures of Cash Flow Information Non-cash transactions: Capital expenditures included in current liabilities $ 245.7 $ 170.4 $ 223.6 Assets acquired under a finance lease 22.4 59.3 26.4 Assets acquired under an operating lease 6.0 10.9 13.4 Reclassification of other property to regulatory assets (1) 607.6 — — Assets recorded for asset retirement obligations (2) 12.0 91.5 54.6 Obligation to developer at formation of joint venture (3) 277.5 69.7 — Purchase contract liability, net of fees and payments (4) 129.4 — — Schedule of interest and income taxes paid: Cash paid for interest on long-term debt, net of interest capitalized amounts $ 322.4 $ 349.0 $ 349.7 Cash paid for interest on finance leases 9.4 11.1 11.3 Cash paid for income taxes, net of refunds (5) 5.4 (1.0) 10.8 (1) See Note 9, "Regulatory Matters," for additional information. (2) See Note 8, "Asset Retirement Obligations," for additional information. (3) Represents investing non-cash activity. See Note 4, "Variable Interest Entities," for additional information. (4) Refer to Note 13, "Equity," for additional information. (5) Amount of refunds in 2020 was greater than the amount of tax payments due to overpayments in 2019.

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts (Tables)	12 Months Ended
	Dec. 31, 2021
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Schedule of Valuation and Qualifying Accounts Disclosure	NISOURCE INC. SCHEDULE II – VALUATION AND QUALIFYING ACCOUNTS Twelve months ended December 31, 2021 Additions ($ in millions) Balance Jan. 1, 2021 Charged to Costs and Expenses Charged to Other Account (1) Deductions for Purposes for which Reserves were Created Balance Dec. 31, 2021 Reserves Deducted in Consolidated Balance Sheet from Assets to Which They Apply: Reserve for accounts receivable $ 52.3 $ 18.3 $ 6.4 $ 53.5 $ 23.5 Reserve for deferred charges and other — — 2.3 — 2.3 Twelve months ended December 31, 2020 Additions ($ in millions) Balance Jan. 1, 2020 Charged to Costs and Expenses Charged to Other Account (1) Deductions for Purposes for which Reserves were Created Balance Dec. 31, 2020 Reserves Deducted in Consolidated Balance Sheet from Assets to Which They Apply: Reserve for accounts receivable $ 19.2 $ 31.6 $ 33.0 $ 31.5 $ 52.3 Reserve for other investments 3.0 — — 3.0 — Twelve months ended December 31, 2019 Additions ($ in millions) Balance Charged to Costs and Expenses Charged to Other Account (1) Deductions for Purposes for which Reserves were Created Balance Reserves Deducted in Consolidated Balance Sheet from Assets to Which They Apply: Reserve for accounts receivable $ 21.1 $ 21.6 $ 41.3 $ 64.8 $ 19.2 Reserve for other investments 3.0 — — — 3.0 (1) Charged to Other Accounts reflects the deferral of bad debt expense to a regulatory asset or the movement of the reserve between short term and long term..

Nature of Operations And Summ_3

Nature of Operations And Summary of Significant Accounting Policies (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Basis Of Accounting Presentation [Line Items]
Number of customers	3,700,000
Other than Temporary Impairment Losses, Investments	$ 0	$ 0	$ 0
Pre-tax rate for allowance for funds used during construction	3.30%	2.60%	3.00%
Inventory valued using LIFO	$ 44.9	$ 42.3
Excess of replacement over LIFO value	(13.6)	(19.6)
Inventory valued using the weighted average cost methodology	$ 282.4	$ 148.8

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Details)	12 Months Ended
	Dec. 31, 2021
Accounting Standards Update 2020-04
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2020-04
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	false
Accounting Standards Update 2021-01
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2021-01
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	false
Accounting Standards Update 2021-10
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2021-10
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	false

Recently Adopted Pronouncements

Recently Adopted Pronouncements (Details) - Accounting Standards Update 2020-06	12 Months Ended
	Dec. 31, 2021	Dec. 15, 2021
Recently Adopted Accounting Pronouncements [Line Items]
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2020-06
Change in Accounting Principle, Accounting Standards Update, Adoption Date		Dec. 15, 2021
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	true

Revenue Recognition (Narrative)

Revenue Recognition (Narrative) (Details)	12 Months Ended
	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Service Area By County	20

Revenue Recognition (Disaggrega

Revenue Recognition (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Customer revenues	$ 4,731.3	$ 4,473.2	$ 5,053.4
Other revenues	168.3	208.5	155.5
Total Operating Revenues	4,899.6	4,681.7	5,208.9
Gas Distribution Operations
Disaggregation of Revenue [Line Items]
Customer revenues	3,126.1	3,032	3,455.2
Other revenues	45.1	96.1	54.5
Total Operating Revenues	3,171.2	3,128.1	3,509.7
Electric Operations
Disaggregation of Revenue [Line Items]
Customer revenues	1,604.4	1,440.4	1,597.4
Other revenues	91.9	95.5	101
Total Operating Revenues	1,696.3	1,535.9	1,698.4
Corporate and Other
Disaggregation of Revenue [Line Items]
Customer revenues	0.8	0.8	0.8
Other revenues	31.3	16.9	0
Total Operating Revenues	32.1	17.7	0.8
Residential
Disaggregation of Revenue [Line Items]
Customer revenues	2,677.3	2,602.8	2,790.6
Residential | Gas Distribution Operations
Disaggregation of Revenue [Line Items]
Customer revenues	2,109.4	2,075	2,309
Residential | Electric Operations
Disaggregation of Revenue [Line Items]
Customer revenues	567.9	527.8	481.6
Residential | Corporate and Other
Disaggregation of Revenue [Line Items]
Customer revenues	0	0	0
Commercial
Disaggregation of Revenue [Line Items]
Customer revenues	1,257.3	1,150.8	1,257.9
Commercial | Gas Distribution Operations
Disaggregation of Revenue [Line Items]
Customer revenues	722.4	670.5	771.3
Commercial | Electric Operations
Disaggregation of Revenue [Line Items]
Customer revenues	534.9	480.3	486.6
Commercial | Corporate and Other
Disaggregation of Revenue [Line Items]
Customer revenues	0	0	0
Industrial
Disaggregation of Revenue [Line Items]
Customer revenues	689.1	624.9	852.9
Industrial | Gas Distribution Operations
Disaggregation of Revenue [Line Items]
Customer revenues	195.7	212.8	245.2
Industrial | Electric Operations
Disaggregation of Revenue [Line Items]
Customer revenues	493.4	412.1	607.7
Industrial | Corporate and Other
Disaggregation of Revenue [Line Items]
Customer revenues	0	0	0
Off-system
Disaggregation of Revenue [Line Items]
Customer revenues	71.3	41	77.7
Off-system | Gas Distribution Operations
Disaggregation of Revenue [Line Items]
Customer revenues	71.3	41	77.7
Off-system | Electric Operations
Disaggregation of Revenue [Line Items]
Customer revenues	0	0	0
Off-system | Corporate and Other
Disaggregation of Revenue [Line Items]
Customer revenues	0	0	0
Miscellaneous
Disaggregation of Revenue [Line Items]
Customer revenues	36.3	53.7	74.3
Miscellaneous | Gas Distribution Operations
Disaggregation of Revenue [Line Items]
Customer revenues	27.3	32.7	52
Miscellaneous | Electric Operations
Disaggregation of Revenue [Line Items]
Customer revenues	8.2	20.2	21.5
Miscellaneous | Corporate and Other
Disaggregation of Revenue [Line Items]
Customer revenues	$ 0.8	$ 0.8	$ 0.8

Revenue Recognition (Customer A

Revenue Recognition (Customer Accounts Receivable) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Revenue Recognition [Abstract]
Customer Accounts Receivable, Billed (Less Reserve)	$ 459.6	$ 400
Customer Accounts Receivable, Unbilled (Less Reserve)	$ 337	$ 327.2

Revenue Recognition (Allowance

Revenue Recognition (Allowance for Credit Losses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Credit Loss	$ 23.5	$ 52.3	$ 13
Current period provisions	7.2	54.6
Write-offs charged against allowance	(54.4)	(29.7)
Recoveries of amounts previously written off	18.4	14.4
Gas Distribution Operations
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Credit Loss	18.9	41.8	9.1
Current period provisions	5.8	45.3
Write-offs charged against allowance	(46.7)	(26.7)
Recoveries of amounts previously written off	18	14.1
Electric Operations
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Credit Loss	3.8	9.7	3.1
Current period provisions	1.4	9.3
Write-offs charged against allowance	(7.7)	(3)
Recoveries of amounts previously written off	0.4	0.3
Corporate and Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for Credit Loss	0.8	0.8	$ 0.8
Current period provisions	0	0
Write-offs charged against allowance	0	0
Recoveries of amounts previously written off	$ 0	$ 0

Variable Interest Entities (Nar

Variable Interest Entities (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021USD ($)RateMW	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Variable Interest Entity [Line Items]
Wind Power Purchase Agreement, Purchase Percentage | Rate	100.00%
Payment to renewable generation asset developer	$ 240.4	$ 85.3	$ 0
Rosewater
Variable Interest Entity [Line Items]
Nameplate Capacity | MW	102
Payment to renewable generation asset developer	$ 7.4	85.3
Indiana Crossroads Wind
Variable Interest Entity [Line Items]
Nameplate Capacity | MW	302
Payment to renewable generation asset developer	$ 233	$ 0

Variable Interest Entities (Sch

Variable Interest Entities (Schedule of Noncontrolling Interest) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling interest in consolidated subsidiaries	$ 325.6	$ 85.6
Rosewater
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling interest in consolidated subsidiaries	88.2	85.6
Indiana Crossroads Wind
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling interest in consolidated subsidiaries	$ 237.4	$ 0

Variable Interest Entities (S_2

Variable Interest Entities (Schedule of Net Income Attributable to Noncontrolling Interest) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Attributable to noncontrolling [Line Items]
Net income attributable to noncontrolling interest	$ 3.9	$ 3.4	$ 0
Rosewater
Income Attributable to noncontrolling [Line Items]
Net income attributable to noncontrolling interest	(4.2)	3.4	0
Indiana Crossroads Wind
Income Attributable to noncontrolling [Line Items]
Net income attributable to noncontrolling interest	$ 8.1	$ 0	$ 0

Variable Interest Entities (S_3

Variable Interest Entities (Schedule of Cash Contributions) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash Contributions Noncontrolling Interest [Line Items]
Obligation to the Developer	$ 277.5	$ 69.7	$ 0
Rosewater
Cash Contributions Noncontrolling Interest [Line Items]
NIPSCO Cash Contribution	0.1	0.7
Tax Equity Partners Cash Contribution	7.5	86.1
Obligation to the Developer	6	69.7
Total Cash Contributions	13.6	156.5
Indiana Crossroads Wind
Cash Contributions Noncontrolling Interest [Line Items]
NIPSCO Cash Contribution	2.7	0
Tax Equity Partners Cash Contribution	237.6
Obligation to the Developer	271.5	0
Total Cash Contributions	$ 511.8	$ 0

Variable Interest Entities (S_4

Variable Interest Entities (Schedule of VIE Assets and Liabilities) (Details) - USD ($) $ in Millions		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
VIE Assets and Liabilities [Abstract]
Net Property, Plant and Equipment		$ 17,881.8	$ 16,619.5
Current assets	[1]	1,920.8	1,659.4
Total Assets		24,156.9	22,040.5	$ 22,659.8
Current liabilities		2,746.2	2,279.4
Asset retirement obligations		469.7	477.1
Other noncurrent liabilities		690.2	515.5
Rosewater
VIE Assets and Liabilities [Abstract]
Net Property, Plant and Equipment		170.1	175.6
Current assets		6.2	1.7
Total Assets		176.3	177.3
Current liabilities		2.5	15.3
Asset retirement obligations		5.7	5.5
Other noncurrent liabilities		0	0.1
Total liabilities		8.2	20.9
Indiana Crossroads Wind
VIE Assets and Liabilities [Abstract]
Net Property, Plant and Equipment		525.8	0
Current assets		8.1	0
Total Assets		533.9	0
Current liabilities		7.5	0
Asset retirement obligations		14.8	0
Other noncurrent liabilities		0	0
Total liabilities		$ 22.3	$ 0
[1]	(1) Includes $695.9 million and $175.6 million in 2021 and 2020, respectively, of net property, plant and equipment assets and $14.3 million and $1.7 million in 2021 and 2020, respectively, of current assets of consolidated VIEs that may be used only to settle obligations of the consolidated VIEs. Refer to Note 4, "Variable Interest Entities" for additional information.

Earnings Per Share (Narrative)

Earnings Per Share (Narrative) (Details)	Apr. 19, 2021$ / shares
Equity Units [Member]
Earnings Per Share [Line Items]
Shares Issued, Price Per Share	$ 24.51

Earnings Per Share (Schedule of

Earnings Per Share (Schedule of Earnings Per Share, Basic and Diluted) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Net Income (Loss) Available to Common Shareholders - Basic	$ 529.8	$ (72.7)	$ 328
Dilutive effect of Equity Units	1.6	0	0
Net Income (Loss) Available to Common Shareholders - Diluted	$ 531.4	$ (72.7)	$ 328
Average common shares outstanding - Basic	393,600	384,300	374,600
Equity Units	22,000	0	0
Shares contingently issuable under employee stock plans	800	0	900
Shares restricted under employee stock plans	300	0	200
ATM Forward agreements	600	0	300
Average Common Shares - Diluted	417,300	384,300	376,000
Basic Earnings (Loss) Per Share	$ 1.35	$ (0.19)	$ 0.88
Diluted Earnings (Loss) Per Share	$ 1.27	$ (0.19)	$ 0.87

Property, Plant and Equipment_2

Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Plant and Equipment Associated with Schahfer Generating Station Retirement		$ 903.8
Depreciation	$ 672.1	655.6	$ 612.2
Regulatory Deferral - Joint Venture	5.3
Capitalized Computer Software, Amortization	49.4	56.7	55.5
Capitalized Computer Software, Gross	181.8	136.4
Capitalized Cloud Computing, Amortization	10	3.4	$ 1.6
Capitalized Cloud Computing, Gross	42.4	$ 12.7
Units 14 and 15
Property, Plant and Equipment [Line Items]
Plant and Equipment Associated with Schahfer Generating Station Retirement	600
Units Not Retired
Property, Plant and Equipment [Line Items]
Plant and Equipment Associated with Schahfer Generating Station Retirement	$ 201.5

Property, Plant And Equipment_3

Property, Plant And Equipment (Schedule Of Property, Plant And Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property Plant and Equipment	$ 25,171.3	$ 24,179.9
Accumulated Depreciation and Amortization	(7,289.5)	(7,560.4)
Net Property, Plant and Equipment	17,881.8	16,619.5
Gas Distribution Utility
Property, Plant and Equipment [Line Items]
Property Plant and Equipment	15,240.6	14,010.2
Accumulated Depreciation and Amortization	(3,490.2)	(3,292.9)
Electric Utility
Property, Plant and Equipment [Line Items]
Property Plant and Equipment	6,754.9	6,478
Accumulated Depreciation and Amortization	(2,433.1)	(2,305)
Common Utility
Property, Plant and Equipment [Line Items]
Property Plant and Equipment	217.8	197.3
Accumulated Depreciation and Amortization	(132.2)	(109.3)
Construction Work In Process
Property, Plant and Equipment [Line Items]
Property Plant and Equipment	808	572.6
Renewable Generation Assets
Property, Plant and Equipment [Line Items]
Property Plant and Equipment	702.4	175.7
Accumulated Depreciation and Amortization	(6.5)	(0.1)
Non-Utility And Other
Property, Plant and Equipment [Line Items]
Property Plant and Equipment	1,447.6	2,746.1
Accumulated Depreciation and Amortization	$ (1,227.5)	$ (1,853.1)

Property, Plant And Equipment P

Property, Plant And Equipment Property, Plant and Equipment (Schedule of Depreciation Provisions For Utility Plant as a Percentage of the Original Cost) (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Electric Operations
Property, Plant and Equipment [Line Items]
Depreciation Provisions For Utility Plant Percentage	3.40%	3.40%	2.80%
Gas Distribution Operations
Property, Plant and Equipment [Line Items]
Depreciation Provisions For Utility Plant Percentage	2.20%	2.30%	2.50%

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill And Other Intangible Assets [Line Items]
Goodwill	$ 1,485.9	$ 1,485.9
Intangible Assets, Net (Excluding Goodwill)	0	0
Amortization of Intangible Assets	0	0	$ 11
Gas Distribution Operations
Goodwill And Other Intangible Assets [Line Items]
Goodwill	$ 1,485.9	$ 1,485.9
Columbia Of Massachusetts
Goodwill And Other Intangible Assets [Line Items]
Goodwill			0
Goodwill, Impairment Loss			204.8
Impairment of Intangible Assets, Finite-lived			$ 209.7

Asset Retirement Obligations (C

Asset Retirement Obligations (Changes In Company's Liability For Asset Retirement Obligations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Beginning Balance	$ 477.1
Accretion recorded as a regulatory asset	16	$ 17.3
Additions	23.2	5.5
Settlements	(11.2)	(13.9)
Change in estimated cash flows	(11.2)	86
Other	0	(16.2)
Asset Retirement Obligation	512.4	495.6	$ 416.9
Ending Balance	$ 469.7	$ 477.1

Regulatory Matters (Narrative)

Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Regulatory Assets and Liabilities Disclosure [Abstract]
Remaining Amounts of Regulatory Assets for which No Return on Investment During Recovery Period is Provided	$ 1,207	$ 1,260.6
Remaining Recovery Period of Regulatory Assets for which No Return on Investment During Recovery Period is Provided	48 years
Columbia of Maryland COVID Relief Funds	$ 0.8

Regulatory Matters (Regulatory

Regulatory Matters (Regulatory Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Regulated Operations [Line Items]
Total Assets	$ 2,492.2	$ 1,930.5
Regulatory Assets, Current	206.2	135.7
Regulatory Assets, Noncurrent	2,286	1,794.8
Unrecognized Pension Benefit And Other Postretirement Benefit Costs
Regulated Operations [Line Items]
Total Assets	512.1	583.3
Other Postretirement Costs
Regulated Operations [Line Items]
Total Assets	74.8	72.4
Environmental Costs
Regulated Operations [Line Items]
Total Assets	45.8	56.6
Regulatory Effects Of Accounting For Income Taxes
Regulated Operations [Line Items]
Total Assets	194.8	194.5
Underrecovered Gas And Fuel Costs
Regulated Operations [Line Items]
Total Assets	73.6	8
Depreciation
Regulated Operations [Line Items]
Total Assets	177.5	192.6
Post-In Service Carrying Charges
Regulated Operations [Line Items]
Total Assets	237.9	228.6
Safety Activity Costs
Regulated Operations [Line Items]
Total Assets	171.9	146
DSM Program
Regulated Operations [Line Items]
Total Assets	39.2	37.8
Retired coal generating stations
Regulated Operations [Line Items]
Total Assets	803.9	204.7
Deferred Derivative Gain (Loss)
Regulated Operations [Line Items]
Total Assets	9.6	54.7
Deferred Property Taxes
Regulated Operations [Line Items]
Total Assets	65.1	62.9
Renewable Energy Program
Regulated Operations [Line Items]
Total Assets	18.5	0
Other Assets
Regulated Operations [Line Items]
Total Assets	$ 67.5	$ 88.4

Regulatory Matters (Regulator_2

Regulatory Matters (Regulatory Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Regulated Operations [Line Items]
Regulatory Liabilities	$ 1,980	$ 2,065.5
Regulatory Liability, Current	137.4	161.3
Regulatory Liability, Noncurrent	1,842.6	1,904.2
Deferred Derivative Gain (Loss)
Regulated Operations [Line Items]
Regulatory Liabilities	34.2	14
Overrecovered Gas And Fuel Costs
Regulated Operations [Line Items]
Regulatory Liabilities	5.4	47.8
Cost Of Removal
Regulated Operations [Line Items]
Regulatory Liabilities	749.5	775.2
Regulatory Effects Of Accounting For Income Taxes
Regulated Operations [Line Items]
Regulatory Liabilities	1,040.8	1,105.1
Other Postretirement Costs
Regulated Operations [Line Items]
Regulatory Liabilities	75.9	69.5
Other Liabilities
Regulated Operations [Line Items]
Regulatory Liabilities	$ 74.2	$ 53.9

Regulatory Matters (Schedule of

Regulatory Matters (Schedule of COVID-19 Regulatory Impact) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Regulated Operations [Line Items]
COVID-19 related regulatory asset	$ 2,492.2	$ 1,930.5
Incremental O&M - COVID | Columbia Of Ohio
Regulated Operations [Line Items]
COVID-19 related regulatory asset	2.1	2
Incremental O&M and Bad Debt-COVID | Columbia Of Pennsylvania
Regulated Operations [Line Items]
COVID-19 related regulatory asset	5.2	5.4
Incremental Bad Debt - COVID | NIPSCO
Regulated Operations [Line Items]
COVID-19 related regulatory asset	2.2	9.2
Incremental Bad Debt - COVID | Columbia Of Virginia
Regulated Operations [Line Items]
COVID-19 related regulatory asset	1.5	0
Incremental Bad Debt - COVID | Columbia Of Maryland
Regulated Operations [Line Items]
COVID-19 related regulatory asset	$ 0.9	$ 0.7

Risk Management Activities (Nar

Risk Management Activities (Narrative) (Details) mMDth in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021USD ($)mMDth	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Derivative [Line Items]
Limit of GCA Volumes	20.00%
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	$ 0	$ 0	$ 0
Minimum
Derivative [Line Items]
Commodity Contract Length	1 year
Maximum
Derivative [Line Items]
Commodity Contract Length	6 years
Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount	$ 500
Natural Gas
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | mMDth	124.5

Risk Management Activities (Sch

Risk Management Activities (Schedule of Derivative Instruments in Statement of Financial Position, Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 24.4	$ 13.2
Derivative Liability	144.2	222.8
Risk Management Assets Current
Derivatives, Fair Value [Line Items]
Derivative Asset	10.6	10.4
Risk Management Assets Noncurrent
Derivatives, Fair Value [Line Items]
Derivative Asset	13.8	2.8
Risk Management Liabilities Current
Derivatives, Fair Value [Line Items]
Derivative Liability	136.8	78.2
Risk Management Liabilities Noncurrent
Derivatives, Fair Value [Line Items]
Derivative Liability	7.4	144.6
Interest rate risk programs | Risk Management Assets Current
Derivatives, Fair Value [Line Items]
Derivative Asset	0	0
Interest rate risk programs | Risk Management Assets Noncurrent
Derivatives, Fair Value [Line Items]
Derivative Asset	0	0
Interest rate risk programs | Risk Management Liabilities Current
Derivatives, Fair Value [Line Items]
Derivative Liability	136.4	70.9
Interest rate risk programs | Risk Management Liabilities Noncurrent
Derivatives, Fair Value [Line Items]
Derivative Liability	0	99.5
Commodity price risk programs | Risk Management Assets Current
Derivatives, Fair Value [Line Items]
Derivative Asset	10.6	10.4
Commodity price risk programs | Risk Management Assets Noncurrent
Derivatives, Fair Value [Line Items]
Derivative Asset	13.8	2.8
Commodity price risk programs | Risk Management Liabilities Current
Derivatives, Fair Value [Line Items]
Derivative Liability	0.4	7.3
Commodity price risk programs | Risk Management Liabilities Noncurrent
Derivatives, Fair Value [Line Items]
Derivative Liability	$ 7.4	$ 45.1

Risk Management Activities (S_2

Risk Management Activities (Schedule of Cash Flow Hedges in AOCI) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net current-period other comprehensive income (loss)	$ 29.9	$ (64.1)	$ (55.4)
Interest rate risk programs
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net current-period other comprehensive income (loss)	25.4
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 0.8
Maximum Length of Time Hedged in Interest Rate Cash Flow Hedge	371 months

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Line Items]
Increase (Decrease) in Effective Tax Rate	(37.90%)	30.20%
Deferred Tax Assets, Operating Loss Carryforwards	$ 545.9	$ 608.5
Deferred Tax Assets, Valuation Allowance	7.8	6.4
Unrecognized Tax Benefits, Income Tax Penalties Expense	0	0	$ 0
Unrecognized Tax Benefits, Income Tax Penalties Accrued	0	$ 0
Massachusetts Business [Domain]
Income Taxes [Line Items]
Deferred Tax Assets, Valuation Allowance	7.8
Internal Revenue Service (IRS)
Income Taxes [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards	464.4
State and Local Jurisdiction
Income Taxes [Line Items]
Deferred Tax Assets, Operating Loss Carryforwards	$ 73.7

Income Taxes (Schedule Of Compo

Income Taxes (Schedule Of Components Of Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current
Federal	$ (0.1)	$ 0.2	$ 0
State	6	11.7	5.2
Total Current	5.9	11.9	5.2
Deferred
Federal	99.2	(0.4)	110.7
State	13.8	(27.4)	9
Total Deferred	113	(27.8)	119.7
Deferred Investment Credits	(1.1)	(1.2)	(1.4)
Income Taxes	$ 117.8	$ (17.1)	$ 123.5

Income Taxes (Schedule Of Reaso

Income Taxes (Schedule Of Reasons Behind Differences In Computation Of Total Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Reasons Behind Differences in Computation of Total Income Taxes [Line Items]
Book income (loss) before income taxes	$ 706.6	$ (31.3)	$ 506.6
Tax expense (benefit) at statutory federal income tax rate, value	$ 148.3	$ (6.6)	$ 106.5
Tax expense (benefit) at statutory federal income tax rate, rate	21.00%	21.00%	21.00%
Increases (reductions) in taxes resulting from:
State income taxes, net of federal income tax benefit, value	$ 14.1	$ (11.7)	$ 10.1
State income taxes, net of federal income tax benefit, rate	2.00%	37.40%	2.00%
Amortization of regulatory liabilities, value	$ (39.1)	$ (38.4)	$ (29.4)
Amortization of regulatory liabilities, rate	(5.50%)	122.70%	(5.80%)
Goodwill impairment, value	$ 0	$ 0	$ 43
Goodwill impairment, rate	0.00%	0.00%	8.50%
Fines and penalties, value	$ 0	$ 11.8	$ 11.5
Fines and penalties, rate	0.00%	(37.70%)	2.30%
Charitable contribution carryover, value	$ 0	$ 0	$ (2.5)
Charitable contribution carryover, rate	0.00%	0.00%	(0.50%)
State regulatory proceedings, value	$ 0	$ 0	$ (9.5)
State regulatory proceedings, rate	0.00%	0.00%	(1.90%)
Employee stock ownership plan dividends and other compensation, value	$ (1.2)	$ (1.3)	$ (2)
Employee stock ownership plan dividends and other compensation, rate	(0.20%)	4.20%	(0.40%)
Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Amount	$ 0	$ 23.3	$ 0
Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Percent	0	(0.745)	0
Effective Income Tax Rate Reconciliation Tax Accrual Adjustments	$ (0.1)	$ 8.9	$ 0
Effective Income Tax Rate Reconciliation, Tax Accrual Adjustments, Percent	0.00%	(28.40%)	0.00%
Effective Income Tax Rate Reconciliation, Tax Credit, Amount	$ (2.1)	$ (2.5)	$ 0
Effective Income Tax Rate Reconciliation, Tax Credit, Percent	(0.30%)	(8.00%)	0.00%
Other adjustments, value	$ (2.1)	$ (0.6)	$ (4.2)
Other adjustments, rate	(0.30%)	1.90%	(0.80%)
Income Taxes	$ 117.8	$ (17.1)	$ 123.5
Income Taxes, rate	16.70%	54.60%	24.40%

Income Taxes (Schedule Of Princ

Income Taxes (Schedule Of Principal Components Of Net Deferred Tax Liability) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Liabilities
Accelerated depreciation and other property differences	$ 2,454.4	$ 2,339.3
Other regulatory assets	308.6	331.8
Total Deferred Tax Liabilities	2,763	2,671.1
Deferred Tax Assets
Other regulatory liabilities and deferred investment tax credits (including TCJA)	284.7	287.8
Pension and other postretirement/postemployment benefits	104.8	118.1
Net operating loss carryforward and AMT credit carryforward	545.9	608.5
Environmental liabilities	22.2	22.6
Other accrued liabilities	42.1	41.5
Other, net	111.7	128.4
Total Deferred Tax Assets	1,111.4	1,206.9
Deferred Tax Assets, Valuation Allowance	(7.8)	(6.4)
Deferred Tax Assets, Net of Valuation Allowance	1,103.6	1,200.5
Net Deferred Tax Liabilities	$ 1,659.4	$ 1,470.6

Income Taxes (Schedule of Unrec

Income Taxes (Schedule of Unrecognized Tax Benefits Roll Forward) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits - Opening Balance	$ 21.7	$ 23.2	$ 1.2
Gross decreases - tax positions in prior period	0	(1.5)	(0.6)
Gross increases - current period tax positions	0	0	22.6
Unrecognized Tax Benefits - Ending Balance	21.7	21.7	23.2
Offset for net operating loss carryforwards	(21.7)	(21.7)	(22.6)
Balance - Less Net Operating Loss Carryforwards	$ 0	$ 0	$ 0.6

Pension and Other Postretirem_3

Pension and Other Postretirement Benefits (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 1,834.4	$ 2,036.8
Funded status of plan	(129.3)	(59.3)
Employer contributions	4	2.9
Settlement loss	11.4	$ 10.5	$ 9.5
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Remeasurement due to Settlement	4
Expected contribution	$ 2.8
Expected return on plan assets	5.20%	5.70%	6.10%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Funded status of plan	$ 262.5	$ 304.4
Employer contributions	19.8	21.6
Settlement loss	0	$ 1.5	$ 0
Expected contribution	$ 21.5
Expected return on plan assets	5.50%	5.67%	5.83%

Pension and Other Postretirem_4

Pension and Other Postretirement Benefits (Schedule Of Portfolio Asset Mix) (Details)	Dec. 31, 2021	Dec. 31, 2020
Minimum | Domestic Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	7.00%	12.00%
Minimum | Domestic Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Minimum | International Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	3.00%	6.00%
Minimum | International Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Minimum | Fixed Income | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	69.00%
Minimum | Fixed Income | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	20.00%
Minimum | Real Estate [Member] | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Minimum | Real Estate [Member] | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Minimum | Real Estate | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Minimum | Real Estate | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Minimum | Short-Term Investments | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Minimum | Short-Term Investments | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Minimum | Private Equity | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Minimum | Private Equity | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Maximum | Domestic Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	27.00%	32.00%
Maximum | Domestic Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	55.00%	55.00%
Maximum | International Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	13.00%	16.00%
Maximum | International Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25.00%	25.00%
Maximum | Fixed Income | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	81.00%
Maximum | Fixed Income | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	100.00%
Maximum | Real Estate [Member] | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	3.00%
Maximum | Real Estate [Member] | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Maximum | Real Estate | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		7.00%
Maximum | Real Estate | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Maximum | Short-Term Investments | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10.00%	10.00%
Maximum | Short-Term Investments | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10.00%	10.00%
Maximum | Private Equity | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	3.00%	5.00%
Maximum | Private Equity | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%

Pension and Other Postretirem_5

Pension and Other Postretirement Benefits (Schedule of Plan Asset Mix Prior Year) (Details)	Dec. 31, 2021	Dec. 31, 2020
Pension Plan | Domestic Equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	7.00%	12.00%
Pension Plan | Domestic Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	27.00%	32.00%
Pension Plan | International Equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	3.00%	6.00%
Pension Plan | International Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	13.00%	16.00%
Pension Plan | Fixed Income | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		59.00%
Pension Plan | Fixed Income | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		71.00%
Pension Plan | Real Estate | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Pension Plan | Real Estate | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		7.00%
Pension Plan | Short-Term Investments | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Pension Plan | Short-Term Investments | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10.00%	10.00%
Pension Plan | Private Equity | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Pension Plan | Private Equity | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	3.00%	5.00%
Other Postretirement Benefits | Domestic Equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Other Postretirement Benefits | Domestic Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	55.00%	55.00%
Other Postretirement Benefits | International Equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Other Postretirement Benefits | International Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25.00%	25.00%
Other Postretirement Benefits | Fixed Income | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		20.00%
Other Postretirement Benefits | Fixed Income | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		100.00%
Other Postretirement Benefits | Real Estate | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Other Postretirement Benefits | Real Estate | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		0.00%
Other Postretirement Benefits | Short-Term Investments | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Other Postretirement Benefits | Short-Term Investments | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10.00%	10.00%
Other Postretirement Benefits | Private Equity | Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%
Other Postretirement Benefits | Private Equity | Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%	0.00%

Pension and Other Postretirem_6

Pension and Other Postretirement Benefits (Schedule Of Pension Plan And Postretirement Plan Asset Mix) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 2,275.4	$ 2,404.1
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of total asset	100.00%	100.00%
Pension Plan | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 1,981.7	$ 2,117.7	$ 2,080.9
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Percentage of total asset	100.00%	100.00%
Other Postretirement Benefits | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 293.7	$ 286.4	$ 261.4
Domestic Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 324.3	$ 446.3
Percentage of total asset	16.40%	21.00%
Domestic Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 118.6	$ 108.8
Percentage of total asset	40.40%	38.00%
International Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 150.9	$ 230.1
Percentage of total asset	7.60%	10.90%
International Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 50.5	$ 48.2
Percentage of total asset	17.20%	16.80%
Fixed Income | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 1,382.3	$ 1,291.2
Percentage of total asset	69.70%	61.00%
Fixed Income | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 118.8	$ 122
Percentage of total asset	40.40%	42.60%
Real Estate | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 37.2	$ 52.9
Percentage of total asset	1.90%	2.50%
Real Estate | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0	$ 0
Percentage of total asset	0.00%	0.00%
Cash/Other [Member] | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 87	$ 97.2
Percentage of total asset	4.40%	4.60%
Cash/Other [Member] | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 5.8	$ 7.4
Percentage of total asset	2.00%	2.60%
Commingled Funds | Short-Term Money Markets | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 55	$ 78.8
Commingled Funds | Short-Term Money Markets | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	5.8	7.6
Commingled Funds | International Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	111.7	176.8
Commingled Funds | International Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	26.1	24.1
Commingled Funds | Fixed Income | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	349.1	337.6
Commingled Funds | United States Equities | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	195.9	279.7
Commingled Funds | United States Equities | Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 14.8	$ 14

Pension and Other Postretirem_7

Pension and Other Postretirement Benefits (Schedule Of Fair Value Of Pension Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		$ 480.4
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 432
Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,032.3	934.4
Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	2,275.4	2,404.1
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	1,975.5	2,110.7
Pension Plan | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items		231.1
Pension Plan | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	177.3
Pension Plan | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	1,033.8	936
Pension Plan | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	0	0
Pension Plan | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,981.7	2,117.7	$ 2,080.9
Pension Plan | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	10.3	11.9
Pension Plan | Cash [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		11.9
Pension Plan | Cash [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	9.7
Pension Plan | Cash [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.6	0
Pension Plan | Cash [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | International Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	150.9	230.1
Pension Plan | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,382.3	1,291.2
Pension Plan | Equity Securities [Member] | International Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.5
Pension Plan | Equity Securities [Member] | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.5
Pension Plan | Equity Securities [Member] | International Equities | Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Equity Securities [Member] | International Equities | Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Equity Securities [Member] | United States Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		2.4
Pension Plan | Equity Securities [Member] | United States Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		2.4
Pension Plan | Equity Securities [Member] | United States Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Equity Securities [Member] | United States Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Fixed Income Securities [Member] | Government
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	387.3	243.4
Pension Plan | Fixed Income Securities [Member] | Government | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Fixed Income Securities [Member] | Government | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Fixed Income Securities [Member] | Government | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	387.3	243.4
Pension Plan | Fixed Income Securities [Member] | Government | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Fixed Income Securities [Member] | Corporate/Other debt securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	645.9	692.6
Pension Plan | Fixed Income Securities [Member] | Corporate/Other debt securities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Fixed Income Securities [Member] | Corporate/Other debt securities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Fixed Income Securities [Member] | Corporate/Other debt securities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	645.9	692.6
Pension Plan | Fixed Income Securities [Member] | Corporate/Other debt securities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | International Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	111.7	176.8
Pension Plan | Commingled Funds | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Commingled Funds | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Commingled Funds | International Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | International Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	349.1	337.6
Pension Plan | Commingled Funds | Fixed Income | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Commingled Funds | Fixed Income | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Commingled Funds | Fixed Income | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | Fixed Income | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | United States Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	195.9	279.7
Pension Plan | Commingled Funds | United States Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Commingled Funds | United States Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Commingled Funds | United States Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | United States Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | Short-Term Money Markets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	55	78.8
Pension Plan | Commingled Funds | Short-Term Money Markets | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Commingled Funds | Short-Term Money Markets | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Commingled Funds | Short-Term Money Markets | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Commingled Funds | Short-Term Money Markets | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Private Equity Limited Partnerships [Member] | U.S. Multi-Strategy [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	10.9	10.9
Pension Plan | Private Equity Limited Partnerships [Member] | U.S. Multi-Strategy [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Private Equity Limited Partnerships [Member] | U.S. Multi-Strategy [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Private Equity Limited Partnerships [Member] | U.S. Multi-Strategy [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Private Equity Limited Partnerships [Member] | U.S. Multi-Strategy [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Private Equity Limited Partnerships [Member] | International Multi-Strategy [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	4.5	6.6
Pension Plan | Private Equity Limited Partnerships [Member] | International Multi-Strategy [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Private Equity Limited Partnerships [Member] | International Multi-Strategy [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Private Equity Limited Partnerships [Member] | International Multi-Strategy [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Private Equity Limited Partnerships [Member] | International Multi-Strategy [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Private Equity Limited Partnerships [Member] | Distressed Opportunities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.1	0.3
Pension Plan | Private Equity Limited Partnerships [Member] | Distressed Opportunities [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Private Equity Limited Partnerships [Member] | Distressed Opportunities [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Private Equity Limited Partnerships [Member] | Distressed Opportunities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Private Equity Limited Partnerships [Member] | Distressed Opportunities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	37.2	52.9
Pension Plan | Real Estate [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Real Estate [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Pension Plan | Real Estate [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Real Estate [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Mutual Funds [Member] | International Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	38.7	55.4
Pension Plan | Mutual Funds [Member] | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		55.4
Pension Plan | Mutual Funds [Member] | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	38.7
Pension Plan | Mutual Funds [Member] | International Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Mutual Funds [Member] | International Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Mutual Funds [Member] | U.S. Multi-Strategy [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	128.4	161.3
Pension Plan | Mutual Funds [Member] | U.S. Multi-Strategy [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		161.3
Pension Plan | Mutual Funds [Member] | U.S. Multi-Strategy [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	128.4
Pension Plan | Mutual Funds [Member] | U.S. Multi-Strategy [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Mutual Funds [Member] | U.S. Multi-Strategy [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan | Mutual Funds [Member] | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0.1
Pension Plan | Mutual Funds [Member] | Fixed Income | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0.1
Pension Plan | Mutual Funds [Member] | Fixed Income | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Pension Plan | Mutual Funds [Member] | Fixed Income | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	293.4	286.4
Other Postretirement Benefits | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items		240.7
Other Postretirement Benefits | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	246.7
Other Postretirement Benefits | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	0	0
Other Postretirement Benefits | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Fair Value Of Plan Assets Before Pending Items	0	0
Other Postretirement Benefits | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	293.7	286.4	$ 261.4
Other Postretirement Benefits | International Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	50.5	48.2
Other Postretirement Benefits | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	118.8	122
Other Postretirement Benefits | Due To Brokers Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	(1.8)	(1.6)
Other Postretirement Benefits | Due To Brokers Net [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Other Postretirement Benefits | Due To Brokers Net [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Other Postretirement Benefits | Due To Brokers Net [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	(1.8)	(1.6)
Other Postretirement Benefits | Due To Brokers Net [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Accrued Investment Income Dividends [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	8	8.6
Other Postretirement Benefits | Accrued Investment Income Dividends [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		8.6
Other Postretirement Benefits | Accrued Investment Income Dividends [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	8
Other Postretirement Benefits | Accrued Investment Income Dividends [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Accrued Investment Income Dividends [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Receivables/Payables
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.3
Other Postretirement Benefits | Receivables/Payables | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Other Postretirement Benefits | Receivables/Payables | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0.3
Other Postretirement Benefits | Receivables/Payables | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Other Postretirement Benefits | Commingled Funds | International Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	26.1	24.1
Other Postretirement Benefits | Commingled Funds | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Other Postretirement Benefits | Commingled Funds | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Other Postretirement Benefits | Commingled Funds | International Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Commingled Funds | International Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Commingled Funds | United States Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	14.8	14
Other Postretirement Benefits | Commingled Funds | United States Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Other Postretirement Benefits | Commingled Funds | United States Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Other Postretirement Benefits | Commingled Funds | United States Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Commingled Funds | United States Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Commingled Funds | Short-Term Money Markets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	5.8	7.6
Other Postretirement Benefits | Commingled Funds | Short-Term Money Markets | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		0
Other Postretirement Benefits | Commingled Funds | Short-Term Money Markets | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0
Other Postretirement Benefits | Commingled Funds | Short-Term Money Markets | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Commingled Funds | Short-Term Money Markets | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Mutual Funds [Member] | International Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	24.4	24.1
Other Postretirement Benefits | Mutual Funds [Member] | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		24.1
Other Postretirement Benefits | Mutual Funds [Member] | International Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	24.4
Other Postretirement Benefits | Mutual Funds [Member] | International Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Mutual Funds [Member] | International Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Mutual Funds [Member] | Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	118.5	121.8
Other Postretirement Benefits | Mutual Funds [Member] | Fixed Income | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		121.8
Other Postretirement Benefits | Mutual Funds [Member] | Fixed Income | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	118.5
Other Postretirement Benefits | Mutual Funds [Member] | Fixed Income | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Mutual Funds [Member] | Fixed Income | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Mutual Funds [Member] | United States Equities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	103.8	94.8
Other Postretirement Benefits | Mutual Funds [Member] | United States Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		94.8
Other Postretirement Benefits | Mutual Funds [Member] | United States Equities | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Recurring
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	103.8
Other Postretirement Benefits | Mutual Funds [Member] | United States Equities | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Other Postretirement Benefits | Mutual Funds [Member] | United States Equities | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Underfunded Plan [Member] | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,981.7	2,117.7
Underfunded Plan [Member] | Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0	$ 0

Pension and Other Postretirem_8

Pension and Other Postretirement Benefits (Schedule of Net Asset Value Per Share) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Net Asset Value Excluded From Fair Value By Input	$ 778.8	$ 941.3
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	12.1	12.1
Private Equity and Real Estate Limited Partnerships
Defined Benefit Plan Disclosure [Line Items]
Net Asset Value Excluded From Fair Value By Input	20.4	22.7
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	12.1	12.1
Commingled Funds | Short-Term Money Markets
Defined Benefit Plan Disclosure [Line Items]
Net Asset Value Excluded From Fair Value By Input	60.8	86.4
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	$ 0	$ 0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency	Daily	Daily
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period	1 day	1 day
Commingled Funds | United States Equities
Defined Benefit Plan Disclosure [Line Items]
Net Asset Value Excluded From Fair Value By Input	$ 210.7	$ 293.7
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	$ 0	$ 0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency	Daily	Monthly
Commingled Funds | United States Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period	5 days	5 days
Commingled Funds | United States Equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period	1 day	1 day
Commingled Funds | International Equities
Defined Benefit Plan Disclosure [Line Items]
Net Asset Value Excluded From Fair Value By Input	$ 137.8	$ 200.9
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	$ 0	$ 0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency	Monthly	Monthly
Commingled Funds | International Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period	30 days	30 days
Commingled Funds | International Equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period	10 days	10 days
Commingled Funds | Fixed Income Funds
Defined Benefit Plan Disclosure [Line Items]
Net Asset Value Excluded From Fair Value By Input	$ 349.1	$ 337.6
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	$ 0	$ 0
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency	Daily	Daily
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period	3 days	3 days

Pension and Other Postretirem_9

Pension and Other Postretirement Benefits (Schedule Of Reconciliation Of The Plans Funded Status And Amounts Reflected) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Noncurrent liabilities	$ (261.5)	$ (303.5)
COVID-19 related regulatory asset	2,492.2	1,930.5
Regulatory Liabilities	1,980	2,065.5
Unrecognized Pension Benefit And Other Postretirement Benefit Costs
Defined Benefit Plan Disclosure [Line Items]
Regulatory Liabilities	0	0
Unrecognized Pension Benefit And Other Postretirement Benefit Costs
Defined Benefit Plan Disclosure [Line Items]
COVID-19 related regulatory asset	512.1	583.3
Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	2,404.1
Fair value of plan assets at end of year	2,275.4	2,404.1
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	2,058.4	2,130.5
Service cost	30.2	32	$ 29.2
Interest cost	31.4	51.6	72.3
Plan participants' contributions	0	0
Plan amendments	0	0
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	(68.7)	140.1
Defined Benefit Plan, Benefit Obligation, Benefits Paid	198.9	174.5
Estimated benefits paid by incurred subsidy	0	0
Spinoff to Eversource	0	(121.3)
Projected benefit obligation at end of year	1,852.4	2,058.4	2,130.5
Actual return on plan assets	58.9	329.9
Employer contributions	4	2.9
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	0	0
Benefits paid	(198.9)	(174.6)
Spinoff to Eversource	0	121.4
Defined Benefit Plan, Funded (Unfunded) Status of Plan	129.3	59.3
Noncurrent assets	159.3	91.4
Current liabilities	(2.8)	(2.9)
Noncurrent liabilities	(27.2)	(29.2)
Net amount recognized at end of year	129.3	59.3
Unrecognized prior service cost	0.3	0.3
Unrecognized actuarial loss	438	497.2
Defined Benefit Plan Amounts Recognized In Other Comprehensive Income Or Regulatory Asset Or Liability	438.3	497.5
Pension Plan | Underfunded Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	2,026.3
Projected benefit obligation at end of year	1,822.4	2,026.3
Fair value of plan assets at beginning of year	2,117.7
Fair value of plan assets at end of year	1,981.7	2,117.7
Defined Benefit Plan, Funded (Unfunded) Status of Plan	159.3	91.4
Pension Plan | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	2,117.7	2,080.9
Fair value of plan assets at end of year	1,981.7	2,117.7	2,080.9
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	590.8	576.5
Service cost	6.2	6.6	5.1
Interest cost	9.9	15.4	19.2
Plan participants' contributions	4.2	4.1
Plan amendments	0.1	0
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	(14.8)	24.8
Defined Benefit Plan, Benefit Obligation, Benefits Paid	40.6	37
Estimated benefits paid by incurred subsidy	0.4	0.4
Spinoff to Eversource	0	0
Projected benefit obligation at end of year	556.2	590.8	576.5
Actual return on plan assets	23.9	36.3
Employer contributions	19.8	21.6
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	4.2	4.1
Benefits paid	(40.6)	(37)
Spinoff to Eversource	0	0
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(262.5)	(304.4)
Noncurrent assets	0	0
Current liabilities	(1)	(0.9)
Net amount recognized at end of year	(262.5)	(304.4)
Unrecognized prior service cost	(7.8)	(10.1)
Unrecognized actuarial loss	88.5	116.4
Defined Benefit Plan Amounts Recognized In Other Comprehensive Income Or Regulatory Asset Or Liability	80.7	106.3
Other Postretirement Benefits | Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	286.4	261.4
Fair value of plan assets at end of year	$ 293.7	$ 286.4	$ 261.4

Pension and Other Postretire_10

Pension and Other Postretirement Benefits (Schedule of Benefit Obligations in Excess of Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 1,834.4	$ 2,036.8
Defined Benefit Plan, Benefit Obligation	1,852.4	2,058.4	$ 2,130.5
Defined Benefit Plan, Funded (Unfunded) Status of Plan	129.3	59.3
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Benefit Obligation	556.2	590.8	$ 576.5
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(262.5)	(304.4)
Underfunded Plan [Member] | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	30	32.1
Defined Benefit Plan, Benefit Obligation	30	32.1
Defined Benefit Plan, Plan Assets, Amount	0	0
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(30)	(32.1)
Underfunded Plan [Member] | Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	1,804.3	2,004.7
Defined Benefit Plan, Benefit Obligation	1,822.4	2,026.3
Defined Benefit Plan, Plan Assets, Amount	1,981.7	2,117.7
Defined Benefit Plan, Funded (Unfunded) Status of Plan	$ 159.3	$ 91.4

Pension and Other Postretire_11

Pension and Other Postretirement Benefits (Schedule Of Significant Actuarial Assumptions In Determining Funded Status Plan) (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	2.76%	2.38%
Rate of Compensation Increases	4.00%	4.00%
Interest Crediting Rates	4.00%	4.00%
Trend for Next Year	0.00%	0.00%
Ultimate Trend	0.00%	0.00%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	2.85%	2.49%
Rate of Compensation Increases	0.00%	0.00%
Interest Crediting Rates	0.00%	0.00%
Trend for Next Year	6.20%	6.69%
Ultimate Trend	4.50%	4.50%
Year Ultimate Trend Reached	2030	2029

Pension and Other Postretire_12

Pension and Other Postretirement Benefits (Schedule Of Expected Payments To Participants In Pension Plan) (Details) $ in Millions	Dec. 31, 2021USD ($)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
2022	$ 157.3
2023	150.4
2024	145.6
2025	143.1
2026	135.7
2027-2031	598.9
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
2022	38.1
2023	37.4
2024	36.9
2025	36.5
2026	35.8
2027-2031	168.7
Postretirement Health Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
2022	0.4
2023	0.4
2024	0.3
2025	0.3
2026	0.3
2027-2031	$ 1.1

Pension and Other Postretire_13

Pension and Other Postretirement Benefits (Components Of The Plans' Net Periodic Benefits Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 30.2	$ 32	$ 29.2
Interest cost	31.4	51.6	72.3
Expected return on assets	(101.6)	(111.6)	(108.8)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	0.1	0.7	0.2
Recognized actuarial loss	21.7	33.8	45.2
Settlement loss	11.4	10.5	9.5
Total Net Periodic Benefits Cost	(6.8)	17	47.6
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service Cost	6.2	6.6	5.1
Interest cost	9.9	15.4	19.2
Expected return on assets	(15.3)	(14.4)	(13.1)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(2.2)	(2.1)	(3.2)
Recognized actuarial loss	4.6	4.9	2
Settlement loss	0	1.5	0
Total Net Periodic Benefits Cost	$ 3.2	$ 11.9	$ 10

Pension and Other Postretire_14

Pension and Other Postretirement Benefits (Schedule Of Key Assumptions That Were Used To Calculate The Net Periodic Benefits Cost) (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount rate - service cost	2.81%	3.39%	4.48%
Discount rate - interest cost	1.57%	2.65%	3.84%
Expected Long-Term Rate of Return on Plan Assets	5.20%	5.70%	6.10%
Rate of Compensation Increases	4.00%	4.00%	4.00%
Interest Crediting Rates	4.00%	4.00%	4.00%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate - service cost	3.00%	3.52%	4.59%
Discount rate - interest cost	1.73%	2.76%	3.94%
Expected Long-Term Rate of Return on Plan Assets	5.50%	5.67%	5.83%
Rate of Compensation Increases	0.00%	0.00%	0.00%
Interest Crediting Rates	0.00%	0.00%	0.00%

Pension and Other Postretire_15

Pension and Other Postretirement Benefits (Schedule Of Changes In Plan Assets And Projected Benefit Obligations Recognized In Other Comprehensive Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension Plan
Net prior service cost/(credit)	$ 0	$ 0
Net actuarial (gain)/loss	(26)	(78.2)
Settlements	(11.4)	(10.5)	$ (9.5)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(0.1)	(0.7)	(0.2)
Less: amortization of net actuarial (gain) loss	(21.7)	(33.8)	(45.2)
Less: gain attributable to spinoff to Eversource	0	(33.1)
Less: prior service cost attributable to spinoff to Eversource	0	(2)
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability	(59.2)	(158.3)
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability	(66)	(141.3)
Other Postretirement Benefits
Net prior service cost/(credit)	0.1	0
Net actuarial (gain)/loss	(23.3)	2.9
Settlements	0	(1.5)	0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	2.2	2.1	3.2
Less: amortization of net actuarial (gain) loss	(4.6)	(4.9)	$ (2)
Less: gain attributable to spinoff to Eversource	0	0
Less: prior service cost attributable to spinoff to Eversource	0	0
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability	(25.6)	(1.4)
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability	$ (22.4)	$ 10.5

Equity (Narrative) (Details)

Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions

Dec. 14, 2021

Dec. 13, 2021

Jun. 11, 2021

Jun. 11, 2018

Sep. 01, 2021

Mar. 17, 2021

Dec. 31, 2018

Dec. 31, 2021

Jun. 15, 2023

Apr. 19, 2021

Feb. 22, 2021

Dec. 31, 2020

Dec. 31, 2019

Aug. 01, 2019

Dec. 05, 2018

Nov. 01, 2018

Forward Contract Indexed to Issuer's Equity [Line Items]

Common Stock Aggregate Sale Price

$ 750

$ 434.4

$ 500

Preferred Stock, Par or Stated Value Per Share

$ 0.01

$ 0.01

Net Process from Sale

$ 835.5

Series A Corporate Units

Forward Contract Indexed to Issuer's Equity [Line Items]

Shares Issued, Price Per Share

$ 100

Corporate Units Contract Annual Rate

7.75%

Shares To Be Issued Under Stock Purchase Contracts

35,200,000

Series C Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Shares To Be Issued Under Stock Purchase Contracts

35,200,000

Series A Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Preferred Stock, Shares Issued

400,000

Preferred Stock, Dividend Rate, Percentage

5.65%

Preferred Stock, Liquidation Preference Per Share

$ 1,000

Preferred Stock, Dividend Rate, Initial Margin

2.843%

Preferred Stock, Dividend Rate, Initial Margin Plus 1.000%

1.00%

Preferred Stock, Amount of Preferred Dividends in Arrears

$ 1

Preferred Stock, Per Share Amounts of Preferred Dividends in Arrears

$ 2.51

Preferred Stock, Liquidation Preference, Value

$ 400

$ 400

$ 400

Series B Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Preferred Stock, Dividend Rate, Percentage

6.50%

Preferred Stock, Liquidation Preference Per Share

$ 25,000

Preferred Stock, Dividend Rate, Initial Margin

3.632%

Preferred Stock, Dividend Rate, Initial Margin Plus 1.000%

1.00%

Preferred Stock, Amount of Preferred Dividends in Arrears

$ 1.4

Preferred Stock, Per Share Amounts of Preferred Dividends in Arrears

$ 72.23

Preferred Stock Depositary Shares Issued

20,000,000

Preferred Stock, Liquidation Preference, Value

$ 500

$ 500

$ 500

Depositary Stock Liquidation Preference

$ 25

Series B-1 Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Preferred Stock, Shares Issued

20,000

Series C Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Preferred Stock, Liquidation Preference Per Share

$ 1,000

Preferred Stock, Liquidation Preference, Value

$ 863

Preferred Stock, Par or Stated Value Per Share

$ 0.01

Undivided Beneficial Ownership Interest, Percent

10.00%

Gross Proceeds | Series A Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Proceeds from Issuance of Preferred Stock and Preference Stock

$ 400

Gross Proceeds | Series B Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Proceeds from Issuance of Preferred Stock and Preference Stock

$ 500

Forward February 21

Forward Contract Indexed to Issuer's Equity [Line Items]

Forward Contract Indexed to Issuer's Equity, Shares

6,672,740

Derivative, Forward Price

$ 21.48

$ 22.48

Forward Contract Indexed to Issuer's Equity, Settlement Alternatives, Cash, at Fair Value

$ 143.3

Forward June 2021

Forward Contract Indexed to Issuer's Equity [Line Items]

Forward Contract Indexed to Issuer's Equity, Shares

5,852,475

Derivative, Forward Price

$ 24.85

$ 25.63

Forward Contract Indexed to Issuer's Equity, Settlement Alternatives, Cash, at Fair Value

$ 145.4

Forward August 2021

Forward Contract Indexed to Issuer's Equity [Line Items]

Forward Contract Indexed to Issuer's Equity, Shares

5,941,598

Derivative, Forward Price

$ 25.25

$ 24.71

Forward Contract Indexed to Issuer's Equity, Settlement Alternatives, Cash, at Fair Value

$ 146.8

Preferred Stock | Series A Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Proceeds from Issuance of Preferred Stock and Preference Stock

$ 393.9

Preferred Stock | Net Proceeds | Series B Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Proceeds from Issuance of Preferred Stock and Preference Stock

$ 486.1

At The Market Program

Forward Contract Indexed to Issuer's Equity [Line Items]

ATM Program Equity Remaining Available for Issuance

$ 300

Subsequent Event | Series A Preferred Stock

Forward Contract Indexed to Issuer's Equity [Line Items]

Preferred Stock, Liquidation Preference Per Share

$ 1,000

Equity (Schedule of Stock Offer

Equity (Schedule of Stock Offering Program) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
At The Market Stock Offering [Line Items]
Proceeds, net of fees (in millions)	$ 299.6	$ 211.4	$ 244.4
At The Market Program
At The Market Stock Offering [Line Items]
Number of shares issued	12,525,215	8,459,430	8,422,498
Average price per share	$ 23.95	$ 23.60	$ 27.75
Proceeds, net of fees (in millions)	$ 288.1	$ 196.5	$ 229.1

Equity (Schedule of Stock by Cl

Equity (Schedule of Stock by Class - Preferred) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Preferred Stock, Shares Outstanding	1,302,500	440,000
Preferred Stock, Value, Outstanding	$ 1,546.5	$ 880
Series A Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Liquidation Preference Per Share	$ 1,000
Preferred Stock, Shares Outstanding	400,000
Preferred Stock, Dividends Per Share, Declared	$ 56.50	$ 56.50	$ 56.50
Preferred Stock, Value, Outstanding	$ 393.9	$ 393.9
Series B Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Liquidation Preference Per Share	$ 25,000
Preferred Stock, Shares Outstanding	20,000
Preferred Stock, Dividends Per Share, Declared	$ 1,625	$ 1,625	1,674.65
Preferred Stock, Value, Outstanding	$ 486.1	$ 486.1
Series C Preferred Stock
Class of Stock [Line Items]
Preferred Stock, Liquidation Preference Per Share	$ 1,000
Preferred Stock, Shares Outstanding	862,500
Preferred Stock, Dividends Per Share, Declared	$ 0	$ 0	$ 0
Preferred Stock, Value, Outstanding	$ 666.5	$ 0

Equity (Schedule of Equity Unit

Equity (Schedule of Equity Units) (Details) - USD ($) shares in Thousands, $ in Millions	Apr. 19, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Equity Units [Line Items]
Net Process from Sale	$ 835.5
Purchase Contract Liability	168.8	$ 129.4	$ 0	$ 0
Payments of Stock Issuance Costs	$ 27
Equity Units Stock Purchase Contract Liability Payment		$ 41.2	$ 0
Series A Corporate Units
Equity Units [Line Items]
Number of shares issued	8,625
Corporate Units Contract Annual Rate	7.75%
Preferred Stock
Equity Units [Line Items]
Payments of Stock Issuance Costs	$ 22.5
Purchase Contract Liability
Equity Units [Line Items]
Payments of Stock Issuance Costs	$ 4.5

Share-Based Compensation (Narra

Share-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended			36 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	May 19, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for awards, shares	9,081,947					9,081,947
Common stock reserved for future awards, shares							10,000,000
Stock-based employee compensation expense	$ 16.7	$ 13.5	$ 16.3
Related tax benefits	4	3.3	4
Excess Tax Benefit from Share-based Compensation, Operating Activities	0.4		0.8
Unrecognized compensation cost related to nonvested awards	$ 25.1					$ 25.1
Weighted-average remaining requisite service period, years	1 year 9 months 18 days
RTSR Modifier	25.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	3.00%
401(k) match, profit sharing and non-elective expense	$ 39.1	37.8	$ 37.5
Excess Tax Expense - Share Based Compensation		$ 0.4
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	285,755
Shares nonvested	572,154	478,227				572,154
Shares vesting period, (years)						3 years
Granted, Weighted Average Grant Date Fair Value	$ 19.83
Restricted Stock Units (RSUs) | Share-based Payment Arrangement, Nonemployee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	66,273					66,273
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	252,673					252,673
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	973,885	528,729	552,389
Shares nonvested	1,798,151	1,384,336				1,798,151
Shares vesting period, (years)						3 years
Granted, Weighted Average Grant Date Fair Value	$ 21.76
Performance Shares | NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares granted	$ 6.5	$ 11.7	$ 11.7
Performance Shares | CVI
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of shares granted		$ 2.6	$ 2.5
2019 Award | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			166,031
Shares nonvested	99,055					99,055
Share-based Compensation Arrangement by Share-based Payment Award, Grant Date Fair Value			$ 4.1
2019 Award | Performance Shares | NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	353,302					353,302
2019 Award | Performance Shares | CVI
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	81,528					81,528
2020 award | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		235,100
Shares nonvested	198,303					198,303
Share-based Compensation Arrangement by Share-based Payment Award, Grant Date Fair Value		$ 6.1
2020 award | Performance Shares | NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	349,686					349,686
2020 award | Performance Shares | CVI
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	80,696					80,696
2021 award | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	285,755
Shares nonvested	274,796					274,796
Share-based Compensation Arrangement by Share-based Payment Award, Grant Date Fair Value	$ 5.7
2021 award | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	582,944
2021 award | Performance Shares | NOEPS
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares nonvested	278,328					278,328
2021 Special award | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	390,941
Subsequent Event | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vesting period, (years)				3 years	3 years
Subsequent Event | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vesting period, (years)				3 years	3 years

Share-Based Compensation (Sched

Share-Based Compensation (Schedule Of Transactions Of Restricted Stock Unit) (Details) - Restricted Stock Units (RSUs)	12 Months Ended
	Dec. 31, 2021$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested, Other Than Options | shares	478,227
Nonvested, Weighted Average Grant Date Fair Value | $ / shares	$ 24.51
Granted, Other Than Options | shares	285,755
Granted, Weighted Average Grant Date Fair Value | $ / shares	$ 19.83
Forfeited, Other Than Options | shares	(36,697)
Forfeited, Weighted Average Grant Date Fair Value | $ / shares	$ 23.72
Vested, Other Than Options | shares	(155,131)
Vested, Weighted Average Grant Date Fair Value | $ / shares	$ 22.66
Nonvested, Other Than Options | shares	572,154
Nonvested, Weighted Average Grant Date Fair Value | $ / shares	$ 22.72

Share-Based Compensation (Sch_2

Share-Based Compensation (Schedule Of Transactions Of Contingent Awards) (Details) - Performance Shares - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested, Other Than Options	1,384,336
Nonvested, Weighted Average Grant Date Fair Value	$ 25.09
Granted, Other Than Options	973,885	528,729	552,389
Granted, Weighted Average Grant Date Fair Value	$ 21.76
Forfeited, Other Than Options	(133,695)
Forfeited, Weighted Average Grant Date Fair Value	$ 25.25
Vested, Other Than Options	(426,375)
Vested, Weighted Average Grant Date Fair Value	$ 22.09
Nonvested, Other Than Options	1,798,151	1,384,336
Nonvested, Weighted Average Grant Date Fair Value	$ 23.78	$ 25.09

Share-Based Compensation (Sch_3

Share-Based Compensation (Schedule of Performance Award Details) (Details) - Performance Shares - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,798,151	1,384,336
NOEPS
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 6.5	$ 11.7	$ 11.7
NOEPS | 2019 Award
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	353,302
NOEPS | 2020 award
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	349,686
NOEPS | 2021 award
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	278,328
CVI
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 2.6	$ 2.5
CVI | 2019 Award
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	81,528
CVI | 2020 award
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	80,696
Relative Total Shareholder Return | 2021 award
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	278,328
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 6.7
Relative Total Shareholder Return | 2021 Special award | Share-based Payment Arrangement, Tranche Two
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	124,200
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 3.2
Relative Total Shareholder Return | 2021 Special award | Share-based Payment Arrangement, Tranche One
Performance Share Details [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	252,082
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 4.8

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	Aug. 18, 2020	Apr. 13, 2020	Sep. 30, 2020	Aug. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt Instrument Tendered				$ 969.3
Loss on early extinguishment of long-term debt					$ 0	$ (243.5)	$ 0
Working Capital Adjustment			$ 5.3
Debt Instrument, Convertible, Conversion Ratio					57.40%
Security interest and other subset of asset					$ 200
Asset sale covenant percentage of consolidated total assets					15.00%
Cross default provision on default relating to any indebtedness					$ 75
Percentage of additional subset of assets capped					10.00%
Senior Notes
Debt Instrument [Line Items]
Face amount of notes		$ 1,000
Maximum
Debt Instrument [Line Items]
Cross default provision on default relating to any indebtedness					$ 50
Minimum
Debt Instrument [Line Items]
Cross default provision on default relating to any indebtedness					$ 5
3.60% Notes Due 2030
Debt Instrument [Line Items]
Interest rate on debt		3.60%
3.60% Notes Due 2030 | Senior Notes
Debt Instrument [Line Items]
Proceeds from Debt, Net of Issuance Costs		$ 987.8
0.95% Notes Due 2025
Debt Instrument [Line Items]
Interest rate on debt	0.95%
0.95% Notes Due 2025 | Senior Notes
Debt Instrument [Line Items]
Face amount of notes	$ 1,250
1.70% Notes Due 2031
Debt Instrument [Line Items]
Interest rate on debt	1.70%
1.70% Notes Due 2031 | Senior Notes
Debt Instrument [Line Items]
Face amount of notes	$ 750
0.95% Notes Due 2025 and 1.70% Notes Due 2031 [Member] | Senior Notes
Debt Instrument [Line Items]
Proceeds from Debt, Net of Issuance Costs	$ 1,980.4
3.65% Notes Due 2023
Debt Instrument [Line Items]
Interest rate on debt			3.65%	3.65%
4.45% Notes Due 2021
Debt Instrument [Line Items]
Interest rate on debt			4.45%	4.45%
2.65% Notes Due 2022
Debt Instrument [Line Items]
Interest rate on debt			2.65%	2.65%
3.85% Notes Due 2023
Debt Instrument [Line Items]
Interest rate on debt			3.85%	3.85%
6.25% Notes Due 2040
Debt Instrument [Line Items]
Interest rate on debt				6.25%
5.95% Notes Due 2041
Debt Instrument [Line Items]
Interest rate on debt				5.95%
5.89% Notes Due 2025
Debt Instrument [Line Items]
Interest rate on debt			5.89%
Senior Note Redeemed August & September 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount			$ 609.3
Loss on early extinguishment of long-term debt			231.8
Note Redeemed September 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount			25
Loss on early extinguishment of long-term debt			$ 11.7
6.26% Notes Due 2028 [Member]
Debt Instrument [Line Items]
Interest rate on debt			6.26%
Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Debt Instrument, Convertible, Conversion Ratio					70.00%

Long-Term Debt (Schedule of Con

Long-Term Debt (Schedule of Consolidated Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Senior Notes	$ 9,003	$ 9,003
Medium-Term Notes	132	132
Finance Lease, Liability	185.6	195
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(79.1)	(86.9)
Long-term Debt, Excluding Current Maturities	$ 9,241.5	9,243.1
NiSource | 0.95% Notes Due 2025
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	0.95%
Senior Notes	$ 1,250	1,250
NiSource | 3.49% Notes due 2027
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.49%
Senior Notes	$ 1,000	1,000
NiSource | 6.78% Notes Due 2027
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	6.78%
Senior Notes	$ 3	3
NiSource | 2.95% Notes Due 2029
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	2.95%
Senior Notes	$ 750	750
NiSource | 3.60% Notes Due 2030
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.60%
Senior Notes	$ 1,000	1,000
NiSource | 1.70% Notes Due 2031
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	1.70%
Senior Notes	$ 750	750
NiSource | 6.25% Notes Due 2040
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	6.25%
Senior Notes	$ 152.6	152.6
NiSource | 5.95% Notes Due 2041
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	5.95%
Senior Notes	$ 347.4	347.4
NiSource | 5.80% Notes Due 2042
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	5.80%
Senior Notes	$ 250	250
NiSource | 5.25% Notes Due 2043
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	5.25%
Senior Notes	$ 500	500
NiSource | 4.80% Notes due 2044
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	4.80%
Senior Notes	$ 750	750
NiSource | 5.65% Notes Due 2045
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	5.65%
Senior Notes	$ 500	500
NiSource | 4.375% Notes due 2047
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	4.38%
Senior Notes	$ 1,000	1,000
NiSource | 3.95% Notes Due 2048
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.95%
Senior Notes	$ 750	750
NiSource | Medium-term Notes
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	7.99%
Medium-Term Notes	$ 49	49
Columbia Of Massachusetts | Medium-term Notes
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	6.37%
Medium-Term Notes	$ 15	15
NIPSCO | Medium-term Notes
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	7.61%
Medium-Term Notes	$ 68	68
NIPSCO | Finance Leases
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	1.86%
Finance Lease, Liability	$ 18.7	16
Columbia Of Ohio | Finance Leases
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	6.15%
Finance Lease, Liability	$ 87.8	91.2
NiSource Corporate Services | Finance Leases
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	1.73%
Finance Lease, Liability	$ 51.4	49.4
Columbia Of Virginia | Finance Leases
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	6.28%
Finance Lease, Liability	$ 17.7	18.4
Columbia Of Kentucky | Finance Leases
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.79%
Finance Lease, Liability	$ 0.2	0.3
Columbia Of Pennsylvania | Finance Leases
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	6.35%
Finance Lease, Liability	$ 9.8	$ 19.7

Short-Term Borrowings (Narrativ

Short-Term Borrowings (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Line of Credit Facility, Amount Outstanding	$ 0	$ 0
Commercial paper outstanding	560	503
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	0
Cash from financing activities	0	353.2
Accounts receivable securitization fees	1.4	$ 2.6	$ 2.6
Accounts Receivable Program
Short-term Debt [Line Items]
Seasonal Limit	270
Commercial Paper
Short-term Debt [Line Items]
Revolving credit facility, maximum	$ 1,500
Short-term Debt, Weighted Average Interest Rate, at Point in Time	0.24%	0.27%
Revolving Credit Facility
Short-term Debt [Line Items]
Revolving credit facility, maximum	$ 1,850

Leases (Narrative) (Details)

Leases (Narrative) (Details)	12 Months Ended
	Dec. 31, 2021
Lessee, Lease, Description [Line Items]
Lessee, Lease Renewal Term	25 years
Lessee, Operating Lease, Renewal Term	1 year
Lessee, Finance Lease, Term of Contract	4 years
Fleet Lease
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	1 year
Minimum | Office Lease
Lessee, Lease, Description [Line Items]
Remaining Lease Term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Term of Contract	1 year
Maximum | Office Lease
Lessee, Lease, Description [Line Items]
Remaining Lease Term	22 years

Leases (Lease Cost) (Details)

Leases (Lease Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finance lease cost
Amortization of right-of-use assets	$ 28.8	$ 23.4
Cash paid for interest on finance leases	9.4	11.1	$ 11.3
Total finance lease cost	38.2	34.5
Operating lease cost	15.6	20.3
Total lease cost	$ 53.8	$ 54.8

Leases (Right-of-Use Assets and

Leases (Right-of-Use Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Net Property, Plant and Equipment	Net Property, Plant and Equipment
Finance Lease, Right-of-Use Asset	$ 165.7	$ 176.8
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Deferred charges and other	Deferred charges and other
Operating Lease, Right-of-Use Asset	$ 33.8	$ 39.9
Total leased assets	$ 199.5	$ 216.7
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Long-term Debt and Lease Obligation, Current	Long-term Debt and Lease Obligation, Current
Finance Lease, Liability, Current	$ 28.1	$ 23.3
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Liabilities, Current	Other Liabilities, Current
Operating Lease, Liability, Current	$ 6.7	$ 10.3
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Long-term Debt and Lease Obligation	Long-term Debt and Lease Obligation
Finance Lease, Liability, Noncurrent	$ 157.5	$ 171.7
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other noncurrent liabilities	Other noncurrent liabilities
Operating Lease, Liability, Noncurrent	$ 27.9	$ 29.9
Total Lease Liability	$ 220.2	$ 235.2

Leases (Lease Information) (Det

Leases (Lease Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Finance Lease, Interest Payment on Liability	$ 9.4	$ 11.1
Operating Lease, Payments	15.4	20.2
Finance Lease, Principal Payments	25.7	18.4
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	22.4	59.3
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 6	$ 10.9
Finance Lease, Weighted Average Remaining Lease Term	10 years 7 months 6 days	11 years 2 months 12 days
Operating Lease, Weighted Average Remaining Lease Term	8 years 6 months	8 years
Finance Lease, Weighted Average Discount Rate, Percent	5.00%	5.10%
Operating Lease, Weighted Average Discount Rate, Percent	3.70%	4.00%

Leases (Lease Maturity) (Detail

Leases (Lease Maturity) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Lease Maturity [Line Items]
Total Future Minimum Lease Payments Due, Next Twelve Months	$ 45.1
Total Future Minimum Lease Payments, Due in Two Years	38.5
Total Future Minimum Lease Payments, Due in Three Years	30.2
Total Future Minimum Lease Payments, Due in Four Years	23.2
Total Future Minimum Lease Payments, Due in Five Years	19.6
Total Future Minimum Lease Payments, Due Thereafter	129.1
Total Future Minimum Lease Payments Due	285.7
Undiscounted Excess Amount	(65.5)
Total Lease Liability	220.2	$ 235.2
Short-term Lease Liability	34.8
Long-term Lease Liability	185.4
Finance Leases, Future Minimum Payments Due, Next Twelve Months	37.2
Finance Leases, Future Minimum Payments Due in Two Years	33.6
Finance Leases, Future Minimum Payments Due in Three Years	25.6
Finance Leases, Future Minimum Payments Due in Four Years	19.2
Finance Leases, Future Minimum Payments Due in Five Years	15.8
Finance Leases, Future Minimum Payments Due Thereafter	112.9
Finance Lease, Liability, Payment, Due	244.3
Finance Lease, Liability, Undiscounted Excess Amount	(58.7)
Finance Lease, Liability	185.6	195
Finance Lease, Liability, Current	28.1	23.3
Finance Lease, Liability, Noncurrent	157.5	171.7
Operating Leases, Future Minimum Payments Due, Next Twelve Months	7.9
Operating Leases, Future Minimum Payments, Due in Two Years	4.9
Operating Leases, Future Minimum Payments, Due in Three Years	4.6
Operating Leases, Future Minimum Payments, Due in Four Years	4
Operating Leases, Future Minimum Payments, Due in Five Years	3.8
Operating Leases, Future Minimum Payments, Due Thereafter	16.2
Lessee, Operating Lease, Liability, Payments, Due	41.4
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(6.8)
Operating Lease, Liability	34.6
Operating Lease, Liability, Current	6.7	10.3
Operating Lease, Liability, Noncurrent	$ 27.9	$ 29.9

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Fair Value Disclosure [Line Items]
Transfers between Fair Value Hierarchies	$ 0	$ 0
Allowance for Credit Loss	(0.2)	(0.5)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Period Increase (Decrease)	0
U.S. Treasury debt securities
Fair Value Disclosure [Line Items]
Allowance for Credit Loss	0	0
Available-for-sale securities, maturities of less than a year	8.2
Corporate/Other debt securities
Fair Value Disclosure [Line Items]
Allowance for Credit Loss	(0.2)	$ (0.5)
Available-for-sale securities, maturities of less than a year	$ 3.8

Fair Value (Fair Value Of Finan

Fair Value (Fair Value Of Financial Assets And Liabilities Measured On A Recurring Basis) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Risk management assets	$ 24.4	$ 13.2
Available-for-sale debt securities	171.8	170.9
Total	196.2	184.1
Risk management liabilities	144.2	222.8
Total	144.2	222.8
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Risk management assets	0	0
Available-for-sale debt securities	0	0
Total	0	0
Risk management liabilities	0	0
Total	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Risk management assets	24.4	13.2
Available-for-sale debt securities	171.8	170.9
Total	196.2	184.1
Risk management liabilities	144.2	222.8
Total	144.2	222.8
Significant Unobservable Inputs (Level 3) [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Risk management assets	0	0
Available-for-sale debt securities	0	0
Total	0	0
Risk management liabilities	0	0
Total	$ 0	$ 0

Fair Value (Available-For-Sale

Fair Value (Available-For-Sale Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value Disclosure [Line Items]
Amortized Cost	$ 169.3	$ 163.9
Gross Unrealized Gains	3.8	8
Gross Unrealized Losses	1.1	0.5
Allowance for Credit Loss	(0.2)	(0.5)
Fair Value	171.8	170.9
U.S. Treasury debt securities
Fair Value Disclosure [Line Items]
Amortized Cost	52.8	33.7
Gross Unrealized Gains	0.1	0.3
Gross Unrealized Losses	0.4	0
Allowance for Credit Loss	0	0
Fair Value	52.5	34
Debt Securities, Available-for-sale, Unrealized Loss Position	36.2	0
Corporate/Other debt securities
Fair Value Disclosure [Line Items]
Amortized Cost	116.5	130.2
Gross Unrealized Gains	3.7	7.7
Gross Unrealized Losses	0.7	0.5
Allowance for Credit Loss	(0.2)	(0.5)
Fair Value	119.3	136.9
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 35.4	$ 13.2

Fair Value (Carrying Amount And

Fair Value (Carrying Amount And Estimated Fair Values Of Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Long-term debt (including current portion), Carrying Amount	$ 9,241.5	$ 9,243.1
Long-term debt (including current portion), Estimated Fair Value	$ 10,415.7	$ 11,034.2

Other Commitments And Conting_3

Other Commitments And Contingencies (Narrative) (Details) $ in Millions	12 Months Ended	28 Months Ended
	Dec. 31, 2021USD ($)RateMW	Dec. 31, 2020USD ($)	Feb. 01, 2022USD ($)
Other Commitments And Contingencies [Line Items]
Wind power purchase agreement capacity | MW	500
Major Rail Operators	3
Line of Credit Facility, Amount Outstanding	$ 0	$ 0
Guarantor Obligations, Current Carrying Value	288.9	40.7
Recorded reserves to cover environmental remediation at various sites	$ 91.1	92.6
Wind Power Purchase Agreement, Purchase Percentage | Rate	100.00%
Restructuring and Related Cost, Expected Cost	$ 42
Subsequent Event
Other Commitments And Contingencies [Line Items]
Guarantor Obligations, Current Carrying Value			$ 485.2
MGP Sites
Other Commitments And Contingencies [Line Items]
Number of waste disposal sites identified by program	54
Liability for estimated remediation costs	$ 85.1	85
Reasonably possible remediation costs variance from reserve	$ 17
Columbia Of Massachusetts
Other Commitments And Contingencies [Line Items]
Pipeline Replacement Expenses		258
Coal Transportation | Maximum
Other Commitments And Contingencies [Line Items]
Long Term Purchase Commitment Expiration Year	2028
Pipeline Service Agreements [Member] | Maximum
Other Commitments And Contingencies [Line Items]
Long Term Purchase Commitment Expiration Year	2038
Pipeline Service Agreements [Member] | Minimum
Other Commitments And Contingencies [Line Items]
Long Term Purchase Commitment Expiration Year	2022
IT Service Agreements [Member] | Maximum
Other Commitments And Contingencies [Line Items]
Long Term Purchase Commitment Expiration Year	2027
Standby Letters of Credit
Other Commitments And Contingencies [Line Items]
Line of Credit Facility, Amount Outstanding	$ 18.9	$ 15.2

Other Commitments and Conting_4

Other Commitments and Contingencies (Contractual Obligation, Fiscal Year Maturity Schedule) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Long-term Purchase Commitment [Line Items]
Long-term Debt, Future Minimum Payments Due	$ 9,135
Long-term Debt, Future Minimum Payments Due, Next Twelve Months	30
Long-term Debt, Future Minimum Payments, Due in Two Years	0
Long-term Debt, Future Minimum Payments, Due in Three Years	0
Long-term Debt, Future Minimum Payments, Due in Four Years	1,260
Long-term Debt, Future Minimum Payments, Due in Five Years	0
Long-term Debt, Future Minimum Payments, Due Thereafter	7,845
Interest Payments on Long-term Debt, Future Minimum Payments Due	5,710
Interest Payments on Long-term Debt, Future Minimum Payments Due, Next Twelve Months	335.7
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Two Years	334.1
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Three Years	334.1
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Four Years	334.1
Interest Payments on Long-term Debt, Future Minimum Payments, Due in Five Years	321.6
Interest Payments on Long-term Debt, Future Minimum Payments, Due Thereafter	4,050.4
Finance Leases, Future Minimum Payments Due	244.3
Finance Leases, Future Minimum Payments Due, Next Twelve Months	37.2
Finance Leases, Future Minimum Payments Due in Two Years	33.6
Finance Leases, Future Minimum Payments Due in Three Years	25.6
Finance Leases, Future Minimum Payments Due in Four Years	19.2
Finance Leases, Future Minimum Payments Due in Five Years	15.8
Finance Leases, Future Minimum Payments Due Thereafter	112.9
Operating Leases, Future Minimum Payments Due	41.4
Operating Leases, Future Minimum Payments Due, Next Twelve Months	7.9
Operating Leases, Future Minimum Payments, Due in Two Years	4.9
Operating Leases, Future Minimum Payments, Due in Three Years	4.6
Operating Leases, Future Minimum Payments, Due in Four Years	4
Operating Leases, Future Minimum Payments, Due in Five Years	3.8
Operating Leases, Future Minimum Payments, Due Thereafter	16.2
Energy Commodity Contracts, Future Minimum Payments Due	68.6
Energy Commodity Contracts, Future Minimum Payments Due, Next Twelve Months	60.4
Energy Commodity Contracts, Future Minimum Payments, Due in Two Years	8.2
Energy Commodity Contracts, Future Minimum Payments, Due in Three Years	0
Energy Commodity Contracts, Future Minimum Payments, Due in Four Years	0
Energy Commodity Contracts, Future Minimum Payments, Due in Five Years	0
Energy Commodity Contracts, Future Minimum Payments, Due Thereafter	0
Service Obligations, Pipeline Service Obligations, Future Minimum Payments Due	1,605
Service Obligations, Pipeline Service Obligations, Future Minimum Payments Due, Next Twelve Months	610.5
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Two Years	366
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Three Years	241
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Four Years	136.1
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due in Five Years	98.7
Service Obligations, Pipeline Service Obligations, Future Minimum Payments, Due Thereafter	152.7
Service Obligations, IT Service Obligations, Future Minimum Payments Due	180.1
Service Obligations, IT Service Obligations, Future Minimum Payments Due, Next Twelve Months	69.5
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Two Years	44.8
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Three Years	35.7
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Four Years	27.6
Service Obligations, IT Service Obligations, Future Minimum Payments, Due in Five Years	2.5
Service Obligations, IT Service Obligations, Future Minimum Payments, Due Thereafter	0
Other Liabilities, Future Minimum Payments Due	553
Other Liabilities, Future Minimum Payments Due, Next Twelve Months	95.6
Other Liabilities, Future Minimum Payments, Due in Two Years	457.4
Other Liabilities, Future Minimum Payments, Due in Three Years	0
Other Liabilities, Future Minimum Payments, Due in Four Years	0
Other Liabilities, Future Minimum Payments, Due in Five Years	0
Other Liabilities, Future Minimum Payments, Due Thereafter	0
Total Future Contractual Obligations Due	17,537.4
Total Future Contractual Obligations Due, Next Twelve Months	1,246.8
Total Future Contractual Obligations, Due in Two Years	1,249
Total Future Contractual Obligations, Due in Three Years	641
Total Future Contractual Obligations, Due in Four Years	1,781
Total Future Contractual Obligations, Due in Five Years	442.4
Total Future Contractual Obligations, Due Thereafter	12,177.2
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(79.1)	$ (86.9)
Finance Lease, Liability, Undiscounted Excess Amount	(58.7)
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(6.8)
Other Commitment, to be Paid, Year One	33.3
Other Commitment, to be Paid, Year Two	30.2
Other Commitment, to be Paid, Year Three	27.2
Other Commitment, to be Paid, Year Four	24
Other Commitment, to be Paid, Year Five	17
Other Commitment, to be Paid, after Year Five	$ 16.1

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss (Components Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	$ 28.4	$ (64.6)	$ (55.9)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1.5	0.5	0.5
Net current-period other comprehensive income (loss)	29.9	(64.1)	(55.4)
Accumulated other comprehensive loss	(126.8)	(156.7)	(92.6)	$ (37.2)
Gains and Losses on Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(3.5)	3.3	6.1
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(0.4)	(0.6)	(0.4)
Net current-period other comprehensive income (loss)	(3.9)	2.7	5.7
Accumulated other comprehensive loss	2.1	6	3.3	(2.4)
Gains and Losses on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	25.3	(70.8)	(64.3)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.1	0.1	0.1
Net current-period other comprehensive income (loss)		(70.7)	(64.2)
Accumulated other comprehensive loss	(122.5)	(147.9)	(77.2)	(13)
Pension and OPEB Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	6.6	2.9	2.3
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1.8	1	0.8
Net current-period other comprehensive income (loss)	8.4	3.9	3.1
Accumulated other comprehensive loss	$ (6.4)	$ (14.8)	$ (18.7)	$ (21.8)

Other, Net (Schedule Of Other N

Other, Net (Schedule Of Other Net) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Other Nonoperating Income (Expense) [Abstract]
Interest income	$ 4	$ 5.5	$ 7.7
AFUDC equity	13.1	9.9	8
Charitable Contributions	(11.5)	(1.5)	(5.1)
Pension and Other Postretirement Non Service Cost	35.5	9.3	(16.5)
Sale of emission reduction credits	0	4.6	0
Miscellaneous	(0.3)	4.3	0.7
Total Other, net	$ 40.8	$ 32.1	$ (5.2)

Interest Expense, Net (Details)

Interest Expense, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Interest Expense [Abstract]
Interest on long-term debt	$ 336.4	$ 354.2	$ 327.7
Interest on short-term borrowings	0.6	14.7	50.8
Debt discount/cost amortization	11	9.1	8.3
Accounts receivable securitization fees	1.4	2.6	2.6
Allowance for borrowed funds used and interest capitalized during construction	(4.6)	(7)	(7.5)
Debt-based post-in-service carrying charges	(14.7)	(14.6)	(18.7)
Other	11	11.7	15.7
Total Interest Expense, net	$ 341.1	$ 370.7	$ 378.9

Segments Of Business (Narrative

Segments Of Business (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2019USD ($)
Goodwill [Line Items]
Number of Reportable Segments	2
Number of counties in which electric service provided by Electric Operations	20
Columbia Of Massachusetts
Goodwill [Line Items]
Goodwill, Impairment Loss		$ 204.8

Segments Of Business (Schedule

Segments Of Business (Schedule Of Operating Income Derived From Revenues And Expenses By Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Operating Revenues	$ 4,899.6	$ 4,681.7	$ 5,208.9
Operating Income	1,006.9	550.8	890.7
Consolidated Depreciation and Amortization	748.4	725.9	717.4
Consolidated Assets	24,156.9	22,040.5	22,659.8
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments	1,940.4	1,720.8	1,867.8
Disposal Group, Not Discontinued Operation, Loss (Gain) on Write-down		412.4
Gas Distribution Operations
Segment Reporting Information [Line Items]
Operating Revenues	3,171.2	3,128.1	3,509.7
Intersegment	3,183.5	3,140.2	3,522.8
Operating Income	617.5	199.1	675.4
Consolidated Depreciation and Amortization	383	363.1	403.2
Consolidated Assets	15,153.7	13,433	14,224.5
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments	1,406.4	1,266.9	1,380.3
Electric Operations
Segment Reporting Information [Line Items]
Operating Revenues	1,696.3	1,535.9	1,698.4
Intersegment	1,697.1	1,536.6	1,699.2
Operating Income	387.8	348.8	406.8
Consolidated Depreciation and Amortization	329.4	321.3	277.3
Consolidated Assets	7,178.9	6,443.1	6,027.6
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments	517.4	422.8	468.9
Corporate and Other
Segment Reporting Information [Line Items]
Operating Revenues	32.1	17.7	0.8
Intersegment	492.4	467.5	468.9
Operating Income	1.6	2.9	(191.5)
Consolidated Depreciation and Amortization	36	41.5	36.9
Consolidated Assets	1,824.3	2,164.4	2,407.7
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments	16.6	31.1	18.6
Unaffiliated | Gas Distribution Operations
Segment Reporting Information [Line Items]
Operating Revenues	3,171.2	3,128.1	3,509.7
Unaffiliated | Electric Operations
Segment Reporting Information [Line Items]
Operating Revenues	1,696.3	1,535.9	1,698.4
Unaffiliated | Corporate and Other
Segment Reporting Information [Line Items]
Operating Revenues	32.1	17.7	0.8
Intersegment | Gas Distribution Operations
Segment Reporting Information [Line Items]
Intersegment	12.3	12.1	13.1
Intersegment | Electric Operations
Segment Reporting Information [Line Items]
Intersegment	0.8	0.7	0.8
Intersegment | Corporate and Other
Segment Reporting Information [Line Items]
Intersegment	460.3	449.8	468.1
Eliminations
Segment Reporting Information [Line Items]
Intersegment	$ (473.4)	$ (462.6)	$ (482)

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 19, 2021
Non-cash transactions:
Capital expenditures included in current liabilities	$ 245.7	$ 170.4	$ 223.6
Assets acquired under a finance lease		59.3	26.4
Assets acquired under an operating lease		10.9	13.4
Reclassification of other property to regulatory assets	607.6	0	0
Assets recorded for asset retirement obligations	12	91.5	54.6
Obligation to the Developer	277.5	69.7	0
Purchase Contract Liability	129.4	0	0	$ 168.8
Schedule of interest and income taxes paid:
Cash paid for interest on long-term debt, net of interest capitalized amounts	322.4	349	349.7
Cash paid for interest on finance leases	9.4	11.1	11.3
Cash paid for income taxes, net of refunds(5)	$ 5.4	$ (1)	$ 10.8

Valuation and Qualifying Acco_2

Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reserve For Accounts Receivable [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning Balance	$ 52.3	$ 19.2	$ 21.1
Valuation Allowances and Reserves, Charged to Cost and Expense	18.3	31.6	21.6
Valuation Allowances and Reserves, Charged to Other Accounts	6.4	33	41.3
Deductions for Purposes for which Reserves were Created	53.5	31.5	64.8
Ending Balance	23.5	52.3	19.2
Reserve For Other Investments [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning Balance	0	3	3
Valuation Allowances and Reserves, Charged to Cost and Expense		0	0
Valuation Allowances and Reserves, Charged to Other Accounts		0	0
Deductions for Purposes for which Reserves were Created		3	0
Ending Balance		0	$ 3
Reserve for Deferred Charges and Other
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning Balance	0
Valuation Allowances and Reserves, Charged to Cost and Expense	0
Valuation Allowances and Reserves, Charged to Other Accounts	2.3
Deductions for Purposes for which Reserves were Created	0
Ending Balance	$ 2.3	$ 0