Fair Value of Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value of Financial Instruments [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The Company’s financial assets and liabilities whose values were recognized at fair value are as follows by level within the fair value hierarchy (in millions):



	As of June 30, 2017
	Level 1		Level 2		Level 3		Other⁽²⁾		Total
Assets:
Nuclear decommissioning trust: ⁽¹⁾
Debt securities:
Domestic government	$	2	$	8	$	—	$	—	$	10
Corporate credit	—		8		—		—		8
Money market funds measured at NAV ⁽²⁾	—		—		—		23		23
Non-qualified benefit plan trust: ⁽³⁾
Money market funds	2		—		—		—		2
Equity securities—domestic	6		—		—		—		6
Debt securities—domestic government	1		—		—		—		1
Collective trust—domestic equity measured at NAV ⁽²⁾	—		—		—		—		—
Assets from price risk management activities: ^{(1) (4)}
Electricity	—		3		2		—		5
Natural gas	—		2		—		—		2
	$	11	$	21	$	2	$	23	$	57
Liabilities from price risk management activities: ^{(1) (4)}
Electricity	$	—	$	2	$	144	$	—	$	146
Natural gas	—		47		11		—		58
	$	—	$	49	$	155	$	—	$	204


(1)	Activities are subject to regulation, with certain gains and losses deferred pursuant to regulatory accounting and included in Regulatory assets or Regulatory liabilities as appropriate.


(2)	Assets are measured at NAV as a practical expedient and not subject to hierarchy level classification disclosure.


(3)	Excludes insurance policies of $27 million, which are recorded at cash surrender value.


(4)	For further information, see Note 4, Price Risk Management.



	As of December 31, 2016
	Level 1		Level 2		Level 3		Other ⁽²⁾		Total
Assets:
Nuclear decommissioning trust: ⁽¹⁾
Debt securities:
Domestic government	$	2	$	10	$	—	$	—	$	12
Corporate credit	—		8		—		—		8
Money market funds measured at NAV ⁽²⁾	—		—		—		21		21
Non-qualified benefit plan trust: ⁽³⁾
Money market funds	1		—		—		—		1
Equity securities—domestic	4		—		—		—		4
Debt securities—domestic government	1		—		—		—		1
Collective trust—domestic equity measured at NAV ⁽²⁾	—		—		—		2		2
Assets from price risk management activities: ^{(1) (4)}
Electricity	—		6		1		—		7
Natural gas	—		15		1		—		16
	$	8	$	39	$	2	$	23	$	72
Liabilities from price risk management activities: ^{(1) (4)}
Electricity	$	—	$	6	$	112	$	—	$	118
Natural gas	—		42		9		—		51
	$	—	$	48	$	121	$	—	$	169


(1)	Activities are subject to regulation, with certain gains and losses deferred pursuant to regulatory accounting and included in Regulatory assets or Regulatory liabilities as appropriate.


(2)	Assets are measured at NAV as a practical expedient and not subject to hierarchy level classification disclosure.


(3)	Excludes insurance policies of $26 million, which are recorded at cash surrender value.


(4)	For further information, see Note 4, Price Risk Management.

Fair Value, Option, Quantitative Disclosures [Table Text Block]

Quantitative information regarding the significant, unobservable inputs used in the measurement of Level 3 assets and liabilities from price risk management activities is presented below:



	Fair Value				Valuation Technique	Significant Unobservable Input	Price per Unit
Commodity Contracts	Assets		Liabilities		Valuation Technique	Significant Unobservable Input	Low		High		Weighted Average
	(in millions)
As of June 30, 2017:
Electricity physical forwards	$	—	$	143	Discounted cash flow	Electricity forward price (per MWh)	$	12.25	$	35.56	$	27.90
Natural gas financial swaps	—		11		Discounted cash flow	Natural gas forward price (per Decatherm)	1.70		3.15		2.14
Electricity financial futures	2		1		Discounted cash flow	Electricity forward price (per MWh)	15.83		29.94		24.37
	$	2	$	155
As of December 31, 2016:
Electricity physical forwards	$	—	$	112	Discounted cash flow	Electricity forward price (per MWh)	$	14.25	$	54.73	$	38.18
Natural gas financial swaps	1		9		Discounted cash flow	Natural gas forward price (per Decatherm)	1.85		4.92		2.64
Electricity financial futures	1		—		Discounted cash flow	Electricity forward price (per MWh)	8.57		33.60		25.10
	$	2	$	121

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

Changes in the fair value of net liabilities from price risk management activities (net of assets from price risk management activities) classified as Level 3 in the fair value hierarchy were as follows (in millions):



	Three Months Ended June 30,					Six Months Ended June 30,
	2017		2016			2017			2016
Balance as of the beginning of the period	144		131			$	119		$	119
Net realized and unrealized losses^*	9		28			35			40
Transfers out of Level 3 to Level 2	—		(1		)	(1		)	(1		)
Balance as of the end of the period	$	153	$	158		$	153		$	158

* Both realized and unrealized losses, of which the unrealized portion is fully offset by the effects of regulatory accounting until settlement of the underlying transactions, are recorded in Purchased power and fuel expense in the condensed consolidated statements of income.

- Definition

Tabular disclosure of the application of the fair value option for measurement and reporting of eligible financial assets and liabilities (as defined), as well as certain other eligible items (as defined) included in the statement of financial position, whether such option is elected for a single eligible item or a group of similar eligible items and is in addition to other disclosures concerning fair value which the company may be required to provide. Such disclosure might be expected to include: (1) for items included in the statement of financial position: (a) for each line item in the statement of financial position that includes an item or items for which the fair value option has been elected, provide the aggregate carrying amount of ineligible items included in each line item in the balance sheet, if any; (b) the difference between the aggregate fair value and the aggregate unpaid principal balance (assuming contractual principal amounts and fair value option elected) of: (i) loans and long-term receivables (other than securities otherwise reported at fair value) and (ii) long-term debt instruments; (c) for loans held as assets for which the fair value option has been elected: (i) the aggregate fair value of loans that are 90 days or more past due, (ii) if the policy is to recognize interest income separately from other changes in fair value, the aggregate fair value of loans in nonaccrual status, and (iii) the difference between the aggregate fair value and the aggregate unpaid principal balance for loans that are 90 days or more past due, in nonaccrual status, or both; (2) for items included in the income statement: (a) the amounts of gains and losses from fair value changes included in earnings and in which line in the income statement those gains and losses are reported whether or not combined with gains and losses from items required to be accounted for at fair value; (b) for loans and other receivables held as assets, the estimated amount of gains or losses included in earnings attributable to changes in instrument-specific credit risk; (c) for liabilities with fair values that have been significantly affected during the reporting period by changes in the instrument-specific credit risk, the estimated amount of gains and losses from fair value changes included in earnings that are attributable to changes in the instrument-specific credit risk; and (3) certain other disclosures as required or determined to be provided.

+ References + Details