Balance Sheet Components (Tables)

6 Months Ended

Jun. 30, 2018

Schedule of Other Current Assets [Table Text Block]

Other current assets consist of the following (in millions):



	June 30, 2018		December 31, 2017
Prepaid expenses	$	38	$	50
Assets from price risk management activities	3		6
Margin deposits	7		11
Other	8		6
Other current assets	$	56	$	73

Schedule of Public Utility Property, Plant, and Equipment [Table Text Block]

Electric utility plant, net consists of the following (in millions):



	June 30, 2018			December 31, 2017
Electric utility plant	$	10,257		$	9,914
Construction work-in-progress	290			391
Total cost	10,547			10,305
Less: accumulated depreciation and amortization	(3,707		)	(3,564		)
Electric utility plant, net	$	6,840		$	6,741

Schedule of Regulatory Assets and Liabilities [Text Block]

Regulatory assets and liabilities consist of the following (in millions):



	June 30, 2018					December 31, 2017
	Current			Noncurrent		Current			Noncurrent
Regulatory assets:
Price risk management	$	48		$	135	$	53		$	151
Pension and other postretirement plans	—			209		—			218
Debt issuance costs	—			17		—			19
Trojan decommissioning activities	—			26		—			—
Other	8			54		9			50
Total regulatory assets	$	56		$	441	$	62		$	438
Regulatory liabilities:
Asset retirement removal costs	$	—		$	955	$	—		$	933
Deferred income taxes	—			272		—			277
Trojan decommissioning activities	2			—		3			—
Asset retirement obligations	—			53		—			52
Tax Reform Deferral⁽¹⁾	—			25		—			—
Other	20			43		28			26
Total regulatory liabilities	$	22	⁽²⁾	$	1,348	$	31	⁽²⁾	$	1,288

(1) Related to the deferral of the 2018 net tax benefits due to the change in corporate tax rate under TCJA.

(2) Included in Accrued expenses and other current liabilities in the condensed consolidated balance sheets.

Other Liabilities Disclosure [Text Block]

Accrued expenses and other current liabilities consist of the following (in millions):



	June 30, 2018		December 31, 2017
Accrued employee compensation and benefits	$	54	$	60
Accrued taxes payable	25		31
Accrued interest payable	27		27
Accrued dividends payable	33		31
Regulatory liabilities—current	22		31
Other	64		61
Total accrued expenses and other current liabilities	$	225	$	241

Schedule of Asset Retirement Obligations [Table Text Block]

Asset retirement obligations (AROs) consist of the following (in millions):



	June 30, 2018		December 31, 2017
Trojan decommissioning activities	$	69	$	45
Utility plant	110		109
Non-utility property	13		13
Asset retirement obligations	$	192	$	167

Pension and Other Postretirement Benefits Disclosure [Text Block]

Components of net periodic benefit cost under the defined benefit pension plan are as follows (in millions):



	Three Months Ended June 30,						Six Months Ended June 30,
	2018			2017			2018			2017
Service cost	$	5		$	4		$	10		$	8
Interest cost*	8			9			16			17
Expected return on plan assets*	(11		)	(10		)	(21		)	(20		)
Amortization of net actuarial loss*	4			3			8			6
Net periodic benefit cost	$	6		$	6		$	13		$	11

* The expense portion of non-service cost components are included in Miscellaneous income (expense), net within Other income on the Company’s condensed consolidated statements of income and comprehensive income pursuant to ASU 2017-07. See Note 1, Basis of Presentation for additional information.