Nuclear Decommissioning (Tables)

9 Months Ended

Sep. 30, 2017

Schedule Of Nuclear Decommissioning [Line Items]

Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block]

The following table provides the pledged assets and payables to ZionSolutions, and withdrawals by ZionSolutions at September 30, 2017 and December 31, 2016:

	Exelon and Generation
	September 30, 2017		December 31, 2016
Carrying value of Zion Station pledged assets	$	57	$	113
Payable to Zion Solutions(a)	53		104
Current portion of payable to Zion Solutions(b)	53		90
Cumulative withdrawals by Zion Solutions to pay decommissioning costs(c)	928		878

_________

(a) Excludes a liability recorded within Exelon’s and Generation’s Consolidated Balance Sheets related to the tax obligation on the unrealized activity associated with the Zion Station NDT funds. The NDT funds will be utilized to satisfy the tax obligations as gains and losses are realized.

(b) Included in Other current liabilities within Exelon’s and Generation’s Consolidated Balance Sheets.

(c) Includes project expenses to decommission Zion Station and estimated tax payments on Zion Station NDT fund earnings.

Schedule of Change in Asset Retirement Obligation [Table Text Block]

The following table provides a rollforward of the nuclear decommissioning ARO reflected on Exelon’s and Generation’s Consolidated Balance Sheets from December 31, 2016 to September 30, 2017:

Nuclear decommissioning ARO at December 31, 2016(a)	$	8,734
Acquisition of FitzPatrick	444
Accretion expense	342
Net decrease due to changes in, and timing of, estimated cash flows	(148		)
Costs incurred to decommission retired plants	(6		)
Nuclear decommissioning ARO at September 30, 2017(a)	$	9,366

_________

(a) Includes $12 million and $10 million for the current portion of the ARO at September 30, 2017 and December 31, 2016, respectively, which is included in Other current liabilities on Exelon’s and Generation’s Consolidated Balance Sheets.

Unrealized Gain (Loss) on Investments [Table Text Block]

The following table provides unrealized gains on NDT funds for the three and nine months ended September 30, 2017 and 2016:

	Exelon and Generation				Exelon and Generation
	Three Months Ended    September 30,				Nine Months Ended   September 30,
	2017		2016		2017		2016
Net unrealized gains on decommissioning trust funds — Regulatory Agreement Units(a)	$	44	$	155	$	253	$	286
Net unrealized gains on decommissioning trust funds — Non-Regulatory Agreement Units(b)(c)	111		116		347		216

_________

(a) Net unrealized gains related to Generation’s NDT funds associated with Regulatory Agreement Units are included in Regulatory liabilities on Exelon’s Consolidated Balance Sheets and Noncurrent payables to affiliates on Generation’s Consolidated Balance Sheets.

(b) Excludes $4 million and $5 million of net unrealized losses related to the Zion Station pledged assets for the three months ended September 30, 2017 and 2016 respectively. Excludes $5 million and $2 million of net unrealized losses related to the Zion Station pledged assets for the nine months ended September 30, 2017 and 2016, respectively. Net unrealized losses related to Zion Station pledged assets are included in Other current liabilities and Payable for Zion Station decommissioning on Exelon’s and Generation’s Consolidated Balance Sheets in 2017 and 2016, respectively.

(c) Net unrealized gains related to Generation’s NDT funds with Non-Regulatory Agreement Units are included within Other, net in Exelon’s and Generation’s Consolidated Statements of Operations and Comprehensive Income.