Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Significant Accounting Policies [Text Block]

Summary of Significant Accounting Policies

The Company's significant accounting policies are detailed in "Note 1. Summary of Significant Accounting Policies" in the Company's 2018 Form 10-K. Changes to the Company's accounting policies as a result of adopting ASU 2016-02, "Leases (Topic 842)," and the related ASU 2018-01 and ASU 2018-11 are discussed in Notes 2 and 4 in this Form 10-Q.

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

Organization

The Company is a holding company with investments in energy and energy services providers offering physical delivery and related services for both electricity and natural gas primarily in the south-central U.S. The Company conducts these activities through two business segments: (i) electric utility and (ii) natural gas midstream operations. The accounts of the Company and its wholly owned subsidiaries are included in the Condensed Consolidated Financial Statements. All intercompany transactions and balances are eliminated in consolidation. The Company generally uses the equity method of accounting for investments where its ownership interest is between 20 percent and 50 percent and it lacks the power to direct activities that most significantly impact economic performance.

The electric utility segment generates, transmits, distributes and sells electric energy in Oklahoma and western Arkansas. Its operations are conducted through OG&E and are subject to regulation by the OCC, the APSC and the FERC. OG&E was incorporated in 1902 under the laws of the Oklahoma Territory and is a wholly owned subsidiary of the Company. OG&E is the largest electric utility in Oklahoma, and its franchised service territory includes Fort Smith, Arkansas and the surrounding communities. OG&E sold its retail natural gas business in 1928 and is no longer engaged in the natural gas distribution business.

The natural gas midstream operations segment represents the Company's investment in Enable through wholly owned subsidiaries and ultimately OGE Holdings. Enable was formed in 2013, and its general partner is equally controlled by the Company and CenterPoint, who each have 50 percent management ownership. Based on the 50/50 management ownership, with neither company having control, the Company accounts for its interest in Enable using the equity method of accounting. Enable is primarily engaged in the business of gathering, processing, transporting and storing natural gas. Enable's natural gas gathering and processing assets are strategically located in four states and serve natural gas production in the Anadarko, Arkoma and Ark-La-Tex Basins. Enable also owns crude oil gathering assets in the Anadarko and Williston Basins. Enable has intrastate natural gas transportation and storage assets that are located in Oklahoma as well as interstate assets that extend from western Oklahoma and the Texas Panhandle to Louisiana, from Louisiana to Illinois and from Louisiana to Alabama.

Basis of Accounting [Text Block]

Basis of Presentation

The Condensed Consolidated Financial Statements included herein have been prepared by the Company, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations; however, the Company believes that the disclosures are adequate to prevent the information presented from being misleading.

In the opinion of management, all adjustments necessary to fairly present the consolidated financial position of the Company at June 30, 2019 and December 31, 2018, the consolidated results of its operations for the three and six months ended June 30, 2019 and 2018 and its consolidated cash flows for the six months ended June 30, 2019 and 2018 have been included and are of a normal, recurring nature except as otherwise disclosed. Management also has evaluated the impact of events occurring after June 30, 2019 up to the date of issuance of these Condensed Consolidated Financial Statements, and these statements contain all necessary adjustments and disclosures resulting from that evaluation.

Due to seasonal fluctuations and other factors, the Company's operating results for the three and six months ended June 30, 2019 are not necessarily indicative of the results that may be expected for the year ending December 31, 2019 or for any future period. The Condensed Consolidated Financial Statements and Notes thereto should be read in conjunction with the audited Consolidated Financial Statements and Notes thereto included in the Company's 2018 Form 10-K.

Schedule of Regulatory Assets and Liabilities

Accounting Records

The accounting records of OG&E are maintained in accordance with the Uniform System of Accounts prescribed by the FERC and adopted by the OCC and the APSC. Additionally, OG&E, as a regulated utility, is subject to accounting principles for certain types of rate-regulated activities, which provide that certain incurred costs that would otherwise be charged to expense can be deferred as regulatory assets, based on the expected recovery from customers in future rates. Likewise, certain actual or anticipated credits that would otherwise reduce expense can be deferred as regulatory liabilities, based on the expected flowback to customers in future rates. Management's expected recovery of deferred costs and flowback of deferred credits generally results from specific decisions by regulators granting such ratemaking treatment.

OG&E records certain incurred costs and obligations as regulatory assets or liabilities if, based on regulatory orders or other available evidence, it is probable that the costs or obligations will be included in amounts allowable for recovery or refund in future rates.

The following table is a summary of OG&E's regulatory assets and liabilities.

	June 30,		December 31,
(In millions)	2019		2018
REGULATORY ASSETS
Current:
Fuel clause under recoveries	$	30.7	$	2.0
Cogeneration credit rider over credit (A)	8.2		—
Production tax credit rider over credit (A)	4.1		6.9
Oklahoma demand program rider under recovery (A)	—		6.4
Other (A)	5.1		3.2
Total current regulatory assets	$	48.1	$	18.5
Non-current:
Benefit obligations regulatory asset	$	172.3	$	188.2
Deferred storm expenses	43.6		36.5
Smart Grid	22.1		25.6
Sooner Dry Scrubbers	21.0		4.5
Unamortized loss on reacquired debt	11.0		11.4
Arkansas deferred pension expenses	7.7		6.8
Other	12.3		12.8
Total non-current regulatory assets	$	290.0	$	285.8
REGULATORY LIABILITIES
Current:
Reserve for tax refund and interim surcharge (B)	$	17.7	$	15.4
SPP cost tracker over recovery (B)	8.0		16.8
Oklahoma demand program rider over recovery (B)	6.2		—
Transmission cost recovery rider over recovery (B)	1.1		2.7
Fuel clause over recoveries	0.1		0.3
Other (B)	3.2		1.4
Total current regulatory liabilities	$	36.3	$	36.6
Non-current:
Income taxes refundable to customers, net	$	921.6	$	937.1
Accrued removal obligations, net	312.9		308.1
Pension tracker	2.2		18.7
Other	6.3		6.8
Total non-current regulatory liabilities	$	1,243.0	$	1,270.7

(A) Included in Other Current Assets in the Condensed Consolidated Balance Sheets.

(B) Included in Other Current Liabilities in the Condensed Consolidated Balance Sheets.    

Management continuously monitors the future recoverability of regulatory assets. When in management's judgment future recovery becomes impaired, the amount of the regulatory asset is adjusted, as appropriate. If OG&E were required to discontinue the application of accounting principles for certain types of rate-regulated activities for some or all of its operations, it could result in writing off the related regulatory assets or liabilities, which could have significant financial effects.

Comprehensive Income (Loss) Note [Text Block]

Accumulated Other Comprehensive Income (Loss)

The following tables summarize changes in the components of accumulated other comprehensive income (loss) attributable to the Company during the six months ended June 30, 2019 and 2018. All amounts below are presented net of tax.

	Pension Plan and Restoration of Retirement Income Plan					Postretirement Benefit Plans
(In millions)	Net Income  (Loss)			Prior Service Cost (Credit)		Net Income (Loss)			Prior Service Cost (Credit)			Total
Balance at December 31, 2018	$	(38.8	)	$	—	$	4.6		$	5.3		$	(28.9	)
Amounts reclassified from accumulated other comprehensive income (loss)	1.7			—		(0.1		)	(0.9		)	0.7
Settlement cost	7.1			—		—			—			7.1
Balance at June 30, 2019	$	(30.0	)	$	—	$	4.5		$	4.4		$	(21.1	)

	Pension Plan and Restoration of Retirement Income Plan					Postretirement Benefit Plans
(In millions)	Net Income  (Loss)			Prior Service Cost (Credit)		Net Income		Prior Service Cost (Credit)			Total
Balance at December 31, 2017	$	(32.7	)	$	—	$	2.5	$	7.0		$	(23.2	)
Amounts reclassified from accumulated other comprehensive income (loss)	1.7			—		—		(0.8		)	0.9
Balance at June 30, 2018	$	(31.0	)	$	—	$	2.5	$	6.2		$	(22.3	)

The following table summarizes significant amounts reclassified out of accumulated other comprehensive income (loss) by the respective line items in net income during the three and six months ended June 30, 2019 and 2018.

Details about Accumulated Other Comprehensive Income (Loss) Components	Amount Reclassified from Accumulated Other Comprehensive Income (Loss)												Affected Line Item in the Condensed Consolidated Statements of Income
	Three Months Ended						Six Months Ended
	June 30,						June 30,
(In millions)	2019			2018			2019			2018
Amortization of Pension Plan and Restoration of Retirement Income Plan items:
Actuarial losses (A)	$	(1.3	)	$	(1.3	)	$	(2.2	)	$	(2.2	)	Other Net Periodic Benefit Expense
Settlement cost (A)	(0.6		)	—			(9.4		)	—			Other Net Periodic Benefit Expense
	(1.9		)	(1.3		)	(11.6		)	(2.2		)	Income Before Taxes
	(0.4		)	(0.3		)	(2.8		)	(0.5		)	Income Tax Expense
	$	(1.5	)	$	(1.0	)	$	(8.8	)	$	(1.7	)	Net Income
Amortization of postretirement benefit plans items:
Prior service credit (A)	$	0.5		$	0.5		$	1.1		$	1.1		Other Net Periodic Benefit Expense
Actuarial gains (A)	0.1			—			0.1			—			Other Net Periodic Benefit Expense
	0.6			0.5			1.2			1.1			Income Before Taxes
	0.1			0.2			0.2			0.3			Income Tax Expense
	$	0.5		$	0.3		$	1.0		$	0.8		Net Income
Total reclassifications for the period, net of tax	$	(1.0	)	$	(0.7	)	$	(7.8	)	$	(0.9	)	Net Income

(A) These accumulated other comprehensive income (loss) components are included in the computation of net periodic benefit cost (see Note 12 for additional information).

Reclassifications [Text Block]

Reclassifications

Certain prior year amounts have been reclassified to conform to the current year presentation.