Incremental Shares Included In Diluted EPS Calculation

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Sale Of Stock, Interest In Notes Issued, Percent

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Sale Of Stock, Quarterly Contract Adjustment Payments, Percent

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Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Face amount or stated value per share of common stock.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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COMMON STOCK - Narrative (Details) - USD ($)	1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
COMMON STOCK - Narrative (Details) - USD ($)	Jun. 30, 2020	Apr. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Par value of common stock (in dollars per share)			$ 1.25		$ 1.25
Shares of common stock outstanding (in shares)			100,587,912		100,587,912			92,394,155
Quarterly contract adjustment payments, percent							3.55%
Incremental shares included in diluted EPS calculation (in shares)			141,062	129,979	124,705	116,904
Corporate Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)							5,750,000
Corporate Unit, stated value per share (in dollars per share)							$ 50
ATM Equity Offering Sales Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per share (in dollars per share)		$ 1.25	$ 24.62		$ 24.62
Consideration received	$ 198,000,000.0	$ 200,000,000.0
Number of shares issued (in shares)	8,122,283
Over-Allotment Option \| Corporate Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued (in shares)							750,000
Series 2018A, Due 2031
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Interest rate							3.70%
Series 2018A, Due 2031 \| Corporate Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Interest in notes issued, percent							5.00%
Convertible
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Interest expense, amortization of debt discount and issuance costs			$ 100,000	$ 100,000	$ 400,000	$ 400,000
Interest expense, coupon			$ 2,700,000	2,700,000	$ 8,000,000.0	8,000,000.0
Effective interest rate (as a percent)			4.00%		4.00%
SJG
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Par value of common stock (in dollars per share)			$ 2.50		$ 2.50
Shares of common stock outstanding (in shares)			2,339,139		2,339,139
Equity infusion			$ 100,000,000.0	$ 0	$ 109,500,000	$ 0