v3.6.0.2

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Schedule of Intangible Assets and Goodwill [Table Text Block]

As of December 31, 2016 and 2015, the components of our intangible assets are reflected in other assets on our Consolidated Balance Sheets and were as follows (in millions):

	2016				2015				Lives
Acquired contracts	$	531			$	521			0 – 9 Years
Customer relationships	420				69				7 – 14 Years
Trademark and trade name	40				41				15 Years
Other	88				88				17 – 23 Years
	1,079				719
Less: Accumulated amortization	429				211
Intangible assets, net	$	650			$	508

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

The estimated aggregate amortization expense of our intangible assets for the next five years is as follows (in millions):

2017	$	155
2018	$	90
2019	$	63
2020	$	44
2021	$	39

Schedule of Jointly Owned Utility Plants

The following table summarizes our proportionate ownership interest in jointly-owned power plants:

As of December 31, 2016		Ownership Interest			Property, Plant & Equipment				Accumulated Depreciation				Construction in Progress
(in millions, except percentages)
Freestone Energy Center		75.0	%		$	382			$	(150	)		$	—
Hidalgo Energy Center		78.5	%		$	255			$	(115	)		$	—

Schedule of Components of Restricted Cash

The table below represents the components of our restricted cash as of December 31, 2016 and 2015 (in millions):

	2016												2015
	Current				Non-Current				Total				Current				Non-Current				Total
Debt service	$	11			$	8			$	19			$	28			$	8			$	36
Construction/major maintenance	45				6				51				50				2				52
Security/project/insurance	114				—				114				136				—				136
Other	3				1				4				2				2				4
Total	$	173			$	15			$	188			$	216			$	12			$	228

Schedule of Total Contractual Future Minimum Lease Receipts

The total contractual future minimum lease rentals for our contracts accounted for as operating leases at December 31, 2016, are as follows (in millions):

2017	$	397
2018	360
2019	320
2020	261
2021	257
Thereafter	604
Total	$	2,199

Future minimum rent payments under these lease agreements, including renewal options and rent escalation clauses, are as follows (in millions):

	Initial Year		2017				2018				2019				2020				2021				Thereafter				Total
Land and other operating leases	various		$	13			$	13			$	13			$	12			$	12			$	176			$	239
Power plant operating lease	2000		22				22				30				—				—				—				74
Total leases			$	35			$	35			$	43			$	12			$	12			$	176			$	313

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Tabular disclosure of proportionate interests in jointly owned utility plants. Includes the amount of plants in service, the accumulated provision for depreciation (if available), the amount of plants under construction, and the proportionate share. The amounts presented may be further subdivided to show amounts applicable to plant subcategories (for example, production, transmission, distribution). Includes statements that the amounts represent the utility's share in each joint plant and that it must provide its own financing. Information concerning two or more generating plants on the same site may be combined. States that the utility's share of direct expenses of the joint plants is included in the corresponding operating expenses on its income statement (for example, fuel, maintenance of plant, other operating expense). If the share of direct expenses is charged to purchased power, then disclose the amount so charged and the proportionate amounts charged to specific operating expenses on the records maintained for the joint plants.

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