The AES Corporation (AES) 10-K 27 Feb 18 2017 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Feb. 21, 2018	Jun. 30, 2017
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	AES
Entity Registrant Name	AES CORP
Entity Central Index Key	874,761
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		660,449,495
Entity current reporting status	Yes
Entity voluntary filers	No
Entity Well Known Seasoned Issuer	Yes
Entity Public Float			$ 7,100

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
CURRENT ASSETS
Cash and cash equivalents	$ 949	$ 1,244
Restricted cash	274	277
Short-term investments	424	530
Accounts receivable, net of allowance for doubtful accounts of $10 and $17, respectively	1,463	1,421
Inventory	562	622
Prepaid expenses	62	72
Other current assets	630	657
Current assets of discontinued operations and held-for-sale businesses	2,034	1,593
Total current assets	6,398	6,416
Property, Plant and Equipment:
Land	502	518
Electric generation, distribution assets and other	24,119	24,911
Accumulated depreciation	(7,942)	(7,919)
Construction in progress	3,617	2,905
Property, plant and equipment, net	20,296	20,415
Other Assets:
Investments in and advances to affiliates	1,197	621
Debt service reserves and other deposits	565	438
Goodwill	1,059	1,157
Other intangible assets, net of accumulated amortization of $441 and $399, respectively	366	287
Deferred income taxes	130	227
Service concession assets, net of accumulated amortization of $206 and $114, respectively	1,360	1,445
Other noncurrent assets	1,741	1,775
Noncurrent assets of discontinued operations and held-for-sale businesses	0	3,343
Total other assets	6,418	9,293
TOTAL ASSETS	33,112	36,124
CURRENT LIABILITIES
Accounts payable	1,371	1,238
Accrued interest	228	216
Accrued and other liabilities	1,232	1,117
Non-recourse debt, including $1,012 and $273, respectively, related to variable interest entities	2,164	1,052
Current liabilities of discontinued operations and held-for-sale businesses	1,033	1,654
Total current liabilities	6,028	5,277
NONCURRENT LIABILITIES
Non-recourse debt, including $1,358 and $1,502 respectively, related to variable interest entities	13,176	13,731
Recourse debt	4,625	4,671
Deferred income taxes	1,006	804
Pension and other postretirement liabilities	230	237
Other noncurrent liabilities	2,365	2,327
Noncurrent liabilities of discontinued operations and held-for-sale businesses	0	2,595
Total noncurrent liabilities	21,402	24,365
Commitments and Contingencies (see Notes 11 and 12)
Redeemable stock of subsidiaries	837	782
THE AES CORPORATION STOCKHOLDERS’ EQUITY
Common stock ($0.01 par value, 1,200,000,000 shares authorized; 816,312,913 issued and 660,388,128 outstanding at December 31, 2017 and 816,061,123 issued and 659,182,232 outstanding at December 31, 2016)	8	8
Additional paid-in capital	8,501	8,592
Accumulated deficit	(2,276)	(1,146)
Accumulated other comprehensive loss	(1,876)	(2,756)
Treasury stock, at cost (155,924,785 and 156,878,891 shares at December 31, 2017 and 2016, respectively)	(1,892)	(1,904)
Total AES Corporation stockholders’ equity	2,465	2,794
NONCONTROLLING INTERESTS	2,380	2,906
Total equity	4,845	5,700
TOTAL LIABILITIES AND EQUITY	$ 33,112	$ 36,124

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 10	$ 17
Other intangible assets, accumulated amortization	441	399
Service Concession Asset, Accumulated Depreciation	$ 206	$ 114
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,200,000,000	1,200,000,000
Common stock, shares issued (in shares)	816,312,913	816,061,123
Common stock, shares outstanding (in shares)	660,388,128	659,182,232
Treasury stock, shares (in shares)	155,924,785	156,878,891
Variable Interest Entity [Line Items]
Non-recourse debt - current balance at variable interest entities	$ 2,164	$ 1,052
Non-recourse debt - noncurrent, balance at variable interest entities	13,176	13,731
Consolidated Variable Interest Entities [Member]
Variable Interest Entity [Line Items]
Non-recourse debt - current balance at variable interest entities	1,012	273
Non-recourse debt - noncurrent, balance at variable interest entities	$ 1,358	$ 1,502

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue:
Regulated	$ 3,109	$ 3,310	$ 3,240
Non-Regulated	7,421	6,971	8,020
Total revenue	10,530	10,281	11,260
Cost of Sales:
Regulated	(2,656)	(2,844)	(3,074)
Non-Regulated	(5,410)	(5,057)	(5,523)
Total cost of sales	(8,066)	(7,901)	(8,597)
Operating margin	2,464	2,380	2,663
General and administrative expenses	(215)	(194)	(196)
Interest expense	(1,170)	(1,134)	(1,145)
Interest income	244	245	256
Loss on extinguishment of debt	(68)	(13)	(182)
Other expense	(57)	(79)	(24)
Other income	120	64	84
Gain (loss) on disposal and sale of businesses	(52)	29	29
Goodwill impairment expense	0	0	(317)
Asset impairment expense	(537)	(1,096)	(285)
Foreign currency transaction gains (losses)	42	(15)	106
Other non-operating expense		0
INCOME FROM CONTINUING OPERATIONS BEFORE TAXES AND EQUITY IN EARNINGS OF AFFILIATES	771	187	989
Income tax expense	(990)	(32)	(412)
Net equity in earnings of affiliates	71	36	105
INCOME (LOSS) FROM CONTINUING OPERATIONS	(148)	191	682
Income (loss) from operations of discontinued businesses, net of income tax benefit (expense) of $(21), $229, and $(53), respectively	(18)	151	80
Net loss from disposal and impairments of discontinued businesses, net of income tax benefit of $0, $266, and $0, respectively	(611)	(1,119)	0
NET INCOME (LOSS)	(777)	(777)	762
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Noncontrolling Interest	359	211	364
Noncontrolling interests:
Less: Income from discontinued operations attributable to noncontrolling interests	(25)	(142)	(92)
Total net income attributable to noncontrolling interests and redeemable stock of subsidiaries	(398)	(364)
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION	(1,161)	(1,130)	306
AMOUNTS ATTRIBUTABLE TO THE AES CORPORATION COMMON STOCKHOLDERS:
Income (loss) from continuing operations, net of tax	(507)	(20)	318
Loss from discontinued operations, net of tax	(654)	(1,110)	(12)
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION	$ (1,161)	$ (1,130)	$ 306
BASIC EARNINGS PER SHARE:
Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax	$ (0.77)	$ (0.04)	$ 0.46
Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax	(0.99)	(1.68)	(0.01)
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION COMMON STOCKHOLDERS	(1.76)	(1.72)	0.45
DILUTED EARNINGS PER SHARE:
Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax	(0.77)	(0.04)	0.46
Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax	(0.99)	(1.68)	(0.02)
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION COMMON STOCKHOLDERS	(1.76)	(1.72)	0.44
DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share)	$ 0.49	$ 0.45	$ 0.41

Consolidated Statements of Ope5

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Income from operations of discontinued businesses, income tax expense (benefit)	$ (21)	$ 229	$ (53)
Gain (loss) from disposal and impairment of discontinued businesses, income tax expense (benefit)	$ 0	$ 266	$ 0

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
NET INCOME (LOSS)	$ (777)	$ (777)	$ 762
Foreign currency translation activity:
Foreign currency translation adjustments, net of income tax benefit (expense) of $17, $1, and $1, respectively	(9)	189	(1,019)
Reclassification to earnings, net of $0 income tax for all periods	643	992	0
Total foreign currency translation adjustments	634	1,181	(1,019)
Derivative activity:
Change in derivative fair value, net of income tax benefit (expense) of $10, $(7) and $16, respectively	(12)	5	(57)
Reclassification to earnings, net of income tax expense of $1, $8 and $11, respectively	50	37	66
Total change in fair value of derivatives	38	42	9
Pension activity:
Change in pension adjustments due to prior service cost, net of income tax expense of $1, $6, and $0 respectively	2	11	1
Change in pension adjustments due to net actuarial gain (loss) for the period, net of income tax benefit (expense) of $6, $106, and $(29), respectively	(21)	(208)	60
Reclassification to earnings, net of income tax expense of $135, $3, and $9, respectively	266	10	16
Total pension adjustments	247	(187)	77
OTHER COMPREHENSIVE INCOME (LOSS)	919	1,036	(933)
COMPREHENSIVE INCOME (LOSS)	142	259	(171)
Less: Comprehensive income attributable to noncontrolling interests	(390)	(262)	(133)
COMPREHENSIVE LOSS ATTRIBUTABLE TO THE AES CORPORATION	$ (248)	$ (3)	$ (304)

Consolidated Statements of Com7

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustments, income tax	$ 17	$ 1	$ 1
Foreign currency, reclassification to earnings, income tax benefit (expense)	0	0	0
Change in derivative fair value, income tax	10	(7)	16
Derivative reclassification to earnings, income tax benefit (expense)	(1)	(8)	(11)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Tax	(1)	(6)	0
Pension, net actuarial gain (loss) for the period, income tax	6	106	(29)
Pension, amortization of net actuarial loss, income tax benefit (expense)	$ (135)	$ (3)	$ (9)

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) shares in Millions, $ in Millions		Total	Common Stock [Member]		Treasury Stock		Additional Paid-in Capital [Member]		Retained Earnings (Accumulated Deficit)		AOCI Attributable to Parent [Member]		Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2014			$ 8		$ (1,371)		$ 8,409		$ 512		$ (3,286)		$ 3,053
Beginning Balance (Shares) at Dec. 31, 2014			814.5		110.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		$ 762	$ 0		$ 0		0		306		0		456
Total foreign currency translation adjustment, net of income tax		(1,019)	0		0		0		0		(674)		(345)
Total change in derivative fair value, net of income tax		9	0		0		0		0		43		(34)
Total pension adjustments, net of income tax		77	0		0		0		0		21		56
OTHER COMPREHENSIVE INCOME (LOSS)		(933)									(610)		(323)
Disposition of businesses			0		0		0		0		0		(41)
Distributions to noncontrolling interests			0		0		(27)		0		0		383
Contributions from noncontrolling interests			0		0		0		0		0		126
Dividends declared on common stock			$ 0		$ 0		0		(280)		0		0
Purchase of treasury stock (shares)			0		39.7
Purchase of treasury stock			$ 0		$ (482)		0		0		0		0
Issuance and exercise of stock-based compensation benefit plans (Shares)			1.3		(1.4)
Issuance and exercise of stock-based compensation benefit plans, net of income tax			$ 0		$ 16		13		0		0		0
Sale of subsidiary shares to noncontrolling interests			0		0		323		(377)		0		119
Acquisition of subsidiary shares from noncontrolling interests							0
Acquisition of a business	[1]		0		0		0		0		0		15
Ending Balance at Dec. 31, 2015			$ 8		$ (1,837)		8,718		143		(3,883)		3,022
Ending Balance (Shares) at Dec. 31, 2015			815.8		149
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 0		$ 0		0		(18)		13		0
Net Income (Loss) Attributable to Noncontrolling Interest		364
Net income (loss)		(777)	0		0		0		(1,130)		0		353
Total foreign currency translation adjustment, net of income tax		1,181	0		0		0		0		1,109		72
Total change in derivative fair value, net of income tax		42	0		0		0		0		30		12
Total pension adjustments, net of income tax		(187)	0		0		0		0		(12)		(175)
OTHER COMPREHENSIVE INCOME (LOSS)		1,036									1,127		(91)
Disposition of businesses			0		0		0		0		0		(2)
Distributions to noncontrolling interests			0		0		10		0		0		430
Contributions from noncontrolling interests			0		0		0		0		0		60
Dividends declared on common stock			0		$ 0		(226)		(71)		0		0
Purchase of treasury stock (shares)					8.7
Purchase of treasury stock			$ 0		$ (79)		0		0		0		0
Issuance and exercise of stock-based compensation benefit plans (Shares)			0.3		(0.8)
Issuance and exercise of stock-based compensation benefit plans, net of income tax			$ 0		$ 12		11		0		0		0
Sale of subsidiary shares to noncontrolling interests			0		0		84		(84)		0		17
Acquisition of subsidiary shares from noncontrolling interests		(2)	0		0		(2)		0		0		(17)
Fair value adjustment (2)	[2]		0		0		17		(4)		0		(17)
Ending Balance at Dec. 31, 2016		5,700	$ 8		$ (1,904)		8,592		(1,146)		(2,756)		2,906
Ending Balance (Shares) at Dec. 31, 2016			816.1		156.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Temporary Equity, Net Income		(11)	$ 0	[1]	$ 0	[1]	0	[1]	0	[1]	0	[1]	11	[1]
Net Income (Loss) Attributable to Noncontrolling Interest		398
Net income (loss)		(777)	0		0		0		(1,161)		0		384
Total foreign currency translation adjustment, net of income tax		634	0		0		0		0		661		(27)
Total change in derivative fair value, net of income tax		38	0		0		0		0		23		15
Total pension adjustments, net of income tax		247	0		0		0		0		229		18
OTHER COMPREHENSIVE INCOME (LOSS)		$ 919									913		6
Disposition of businesses			0		0		0		0		0		(666)
Distributions to noncontrolling interests			0		0		0		0		0		426
Contributions from noncontrolling interests			0		0		0		0		0		11
Dividends declared on common stock			$ 0		$ 0		(324)		0		0		0
Purchase of treasury stock (shares)		0
Issuance and exercise of stock-based compensation benefit plans (Shares)			0.2		(1)
Issuance and exercise of stock-based compensation benefit plans, net of income tax			$ 0		$ 12		5		0		0		0
Sale of subsidiary shares to noncontrolling interests			0		0		13		0		7		83
Acquisition of subsidiary shares from noncontrolling interests		$ 240	0		0		240		0		(40)		68
Fair value adjustment (2)	[2]		0	[3]	0		(25)		0		0		0
Ending Balance at Dec. 31, 2017		4,845	$ 8		$ (1,892)		8,501		(2,276)		(1,876)		2,380
Ending Balance (Shares) at Dec. 31, 2017			816.3		155.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Temporary Equity, Net Income		$ 14	$ 0	[1]	$ 0	[1]	0	[1]	0	[1]	0	[1]	14	[1]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 0		$ 0		$ 0		$ 31		$ 0		$ 0
[1]	Net income attributable to noncontrolling interest of $398 million and net loss attributable to redeemable stock of subsidiaries of $14 million for the year ended December 31, 2017. Net income attributable to noncontrolling interest of $364 million and net loss attributable to redeemable stock of subsidiaries of $11 million for the year ended December 31, 2016.
[2]	Adjustment to the carrying amount of noncontrolling interest and redeemable stock of subsidiaries to fair value.
[3]	Fair value of a tax equity partner's right to preferential returns recognized as a result of the acquisition of Solar Power PR, LLC, which was previously accounted for as an equity method investment

Consolidated Statements of Cash

Consolidated Statements of Cash Flows $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
OPERATING ACTIVITIES:
Net income (loss)	$ (777)	$ (777)	$ 762
Adjustments to net income (loss):
Depreciation and amortization	1,169	1,176	1,144
Loss (gain) on sales and disposals of businesses	52	(29)	(29)
Impairment expenses	537	1,098	602
Deferred income taxes	672	(793)	(50)
Provisions for (reversals of) contingencies	34	48	(72)
Loss on extinguishment of debt	68	20	186
Loss on sale and disposal of assets	43	38	20
Net loss from disposal and impairments of discontinued businesses	(611)	(1,383)	0
Other	146	168	8
Changes in operating assets and liabilities:
(Increase) decrease in accounts receivable	(177)	237	(378)
(Increase) decrease in inventory	(28)	42	(26)
(Increase) decrease in prepaid expenses and other current assets	107	870	655
(Increase) decrease in other assets	(295)	(251)	(1,305)
Increase (decrease) in accounts payable and other current liabilities	163	(620)	31
Increase (decrease) in income tax payables, net and other tax payables	53	(199)	53
Increase (decrease) in other liabilities	111	473	533
Net cash provided by operating activities	2,489	2,884	2,134
INVESTING ACTIVITIES:
Capital expenditures	(2,177)	(2,345)	(2,308)
Acquisitions of businesses, net of cash acquired, and equity method investments	(625)	(55)	(17)
Proceeds from the sale of businesses, net of cash sold, and equity method investments	108	631	138
Sale of short-term investments	3,540	4,904	4,851
Payments for Advance to Affiliate	89	6	3
Purchase of short-term investments	(3,310)	(5,151)	(4,801)
Increase in restricted cash, debt service reserves, and other assets	(135)	(61)	(159)
Other investing	(61)	(25)	(67)
Net cash used in investing activities	(2,749)	(2,108)	(2,366)
FINANCING ACTIVITIES:
Borrowings under the revolving credit facilities	2,156	1,465	959
Repayments under the revolving credit facilities	(1,742)	(1,433)	(937)
Issuance of recourse debt	1,025	500	575
Repayments of recourse debt	(1,353)	(808)	(915)
Issuance of non-recourse debt	3,222	2,978	4,248
Repayments of non-recourse debt	(2,360)	(2,666)	(3,312)
Payments for financing fees	(100)	(105)	(90)
Distributions to noncontrolling interests	(424)	(476)	(326)
Contributions from noncontrolling interests and redeemable security holders	73	190	126
Proceeds from the sale of redeemable stock of subsidiaries	0	134	461
Dividends paid on AES common stock	(317)	(290)	(276)
Payments for financed capital expenditures	(179)	(113)	(150)
Purchase of treasury stock	0	(79)	(482)
Proceeds from sales to noncontrolling interests, net of transaction costs	94	0	154
Other financing	(52)	(44)	(7)
Net cash provided by (used in) financing activities	43	(747)	28
Effect of exchange rate changes on cash	3	9	(52)
Decrease (increase) in cash of discontinued operations and held-for-sale businesses	(81)	(12)	25
Total increase (decrease) in cash and cash equivalents	(295)	26	(231)
Cash and cash equivalents, beginning	1,244	1,218
Cash and cash equivalents, ending	949	1,244	1,218
SUPPLEMENTAL DISCLOSURES:
Cash payments for interest, net of amounts capitalized	1,196	1,273	1,265
Cash payments for income taxes, net of refunds	377	487	388
SCHEDULE OF NONCASH INVESTING AND FINANCING ACTIVITIES:
Assets acquired through capital lease and other liabilities	0	5	18
Dividends declared but not yet paid	86	174	135
NonCash Restructuring and Recapitalization	279	0	0
Non-Cash Long Term Receivables	$ 75	$ 0	$ 0

General and Summary of Signific

General and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
GENERAL AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	GENERAL AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES The AES Corporation is a holding company (the "Parent Company") that, through its subsidiaries and affiliates, (collectively, "AES" or "the Company") operates a geographically diversified portfolio of electricity generation and distribution businesses. Generally, the liabilities of individual operating entities are non-recourse to the Parent Company and are isolated to the operating entities. Most of our operating entities are structured as limited liability entities, which limit the liability of shareholders. The structure is generally the same regardless of whether a subsidiary is consolidated under a voting or variable interest model. The preparation of these consolidated financial statements is in conformity with accounting principles generally accepted in the United States of America ("US GAAP"). PRINCIPLES OF CONSOLIDATION — The consolidated financial statements of the Company include the accounts of The AES Corporation and its controlled subsidiaries. Furthermore, VIEs in which the Company has an ownership interest and is the primary beneficiary, thus controlling the VIE, have been consolidated. Intercompany transactions and balances are eliminated in consolidation. Investments in entities where the Company has the ability to exercise significant influence, but not control, are accounted for using the equity method of accounting. NONCONTROLLING INTERESTS — Noncontrolling interests are classified as a separate component of equity in the Consolidated Balance Sheets and Consolidated Statements of Changes in Equity. Additionally, net income and comprehensive income attributable to noncontrolling interests are reflected separately from consolidated net income and comprehensive income on the Consolidated Statements of Operations and Consolidated Statements of Changes in Equity. Any change in ownership of a subsidiary while the controlling financial interest is retained is accounted for as an equity transaction between the controlling and noncontrolling interests (unless the transaction qualifies as a sale of in-substance real estate). Losses continue to be attributed to the noncontrolling interests, even when the noncontrolling interests' basis has been reduced to zero. Equity securities with redemption features that are not solely within the control of the issuer are classified outside of permanent equity. Generally, initial measurement will be at fair value. Subsequent measurement and classification vary depending on whether the instrument is probable of becoming redeemable. Where the equity instrument is not probable of becoming redeemable subsequent allocation of income and dividends is classified in permanent equity. For those securities where it is probable that the instrument will become redeemable or that are currently redeemable, AES recognizes changes in the fair value at each accounting period against retained earnings subject to the floor of the initial fair value. Further, the allocation of income and dividends, as well as the adjustment to fair value, is classified outside permanent equity. Amounts that are mandatory redeemable are classified as a liability. EQUITY METHOD INVESTMENTS — Investments in entities over which the Company has the ability to exercise significant influence, but not control, are accounted for using the equity method of accounting and reported in Investments in and advances to affiliates on the Consolidated Balance Sheets. The Company’s proportionate share of the net income or loss of these companies is included in our results of operations. The Company utilizes the cumulative earning approach to determine whether distributions received from equity method investees are returns on investment or returns of investment. The Company discontinues the application of the equity method when an investment is reduced to zero and the Company is not otherwise committed to provide further financial support to the investee. The Company resumes the application of the equity method accounting to the extent that net income is greater than the share of net losses not previously recorded. Upon acquiring the investment, we determine the fair value of the identifiable assets and assumed liabilities and the basis difference between each fair value and the carrying amount of the corresponding asset or liability in the financial statements of the investee. The AES share of the amortization of the basis difference is recognized in our net equity in earnings of affiliates over the life of the asset or liability. The Company periodically assesses if impairment indicators exist at our equity method investments. When an impairment is observed, any excess of the carrying amount over its estimated fair value is recognized as impairment expense when the loss in value is deemed other-than-temporary and included in Other non-operating expense in the Consolidated Statements of Operations. ALLOCATION OF EARNINGS — Certain of the Company's businesses are subject to profit-sharing arrangements where the allocation of cash distributions and the sharing of tax benefits are not based on fixed ownership percentages. These arrangements exist for certain renewable generation partnerships to designate different allocations of value among investors, where the allocations change in form or percentage over the life of the partnership. For these businesses, the Company uses the hypothetical liquidation at book value (“HLBV”) method when it is a reasonable approximation of the profit-sharing arrangement. The HLBV method calculates the proceeds that would be attributable to each partner based on the liquidation provisions of the respective operating partnership agreement if the partnership was to be liquidated at book value at the balance sheet date. Each partner’s share of income in the period is equal to the change in the amount of net equity they are legally able to claim based on a hypothetical liquidation of the entity at the end of a reporting period compared to the beginning of that period, adjusted for any capital transactions. The HLBV method is used both to allocate the equity earnings attributable to AES when the Company accounts for the renewable business as an equity method investment and to calculate the earnings attributable to noncontrolling interest when the business is consolidated by AES. Where, prior to the commencement of operating activities for a respective renewable energy facility, HLBV results in an immediate decrease in the hypothetical liquidation proceeds attributable to the tax equity investor due to the recognition of ITCs or other adjustments as required by the U.S. Internal Revenue Code, the Company records the impact (sometimes referred to as the ‘Day one gain’) to income in the same period. USE OF ESTIMATES — US GAAP requires the Company to make estimates and assumptions that affect the asset and liability balances reported as of the date of the consolidated financial statements, as well as the revenues and expenses recognized during the reporting period. Actual results could differ from those estimates. Items subject to such estimates and assumptions include: the carrying amount and estimated useful lives of long-lived assets; asset retirement obligations; impairment of goodwill, long-lived assets and equity method investments; valuation allowances for receivables and deferred tax assets; the recoverability of regulatory assets; regulatory liabilities; the fair value of financial instruments; the fair value of assets and liabilities acquired in a business combination; the measurement of equity method investments or noncontrolling interest using the HLBV method for certain renewable generation partnerships; the determination of whether a sale of noncontrolling interests is considered to be a sale of in-substance real estate (as opposed to an equity transaction); pension liabilities; environmental liabilities; the impact of U.S. tax reform; and potential litigation claims and settlements. HELD-FOR-SALE BUSINESSES — A business classified as held-for-sale is reflected on the balance sheet at the lower of its carrying amount or estimated fair value less cost to sell. A loss is recognized if the carrying amount of the business exceeds its estimated fair value less cost to sell. This loss is limited to the carrying value of long lived assets until the completion of the sale, at which point, any additional loss is recognized. If the fair value of the business subsequently exceeds the carrying amount while the business is still held-for-sale, any impairment expense previously recognized will be reversed up to the lower of the previously recognized expense or the subsequent excess. Assets and liabilities related to a business classified as held-for-sale are segregated in the current balance sheet in the period in which the business is classified as held-for-sale. Assets and liabilities of held-for-sale businesses are classified as current when they are expected to be disposed of within twelve months. Transactions between the business held-for-sale and businesses that are expected to continue to exist after the disposal are not eliminated to appropriately reflect the continuing operations and balances held-for-sale. See Note 22 — Held-for-Sale Businesses and Dispositions for further information. DISCONTINUED OPERATIONS — Discontinued operations reporting occurs only when the disposal of a business or a group of businesses represents a strategic shift that has (or will have) a major effect on the Company's operations and financial results. The Company reports financial results for discontinued operations separately from continuing operations to distinguish the financial impact of disposal transactions from ongoing operations. Prior period amounts in the statement of operations and balance sheet are retrospectively revised to reflect the businesses determined to be discontinued operations. The cash flows of businesses that are determined to be discontinued operations are included within the relevant categories within operating, investing and financing activities on the face of the Statements of Cash Flows. Transactions between the businesses determined to be discontinued operations and businesses that are expected to continue to exist after the disposal are not eliminated to appropriately reflect the continuing operations and balances held for sale. The results of discontinued operations include any gain or loss recognized on closing or adjustment of the carrying amount to fair value less cost to sell, including gains or losses associated with noncontrolling interests upon completion of the disposal transaction. See Note 21 — Discontinued Operations for further information. RECLASSIFICATIONS — To comply with newly adopted accounting standards, certain prior period amounts in the consolidated financial statements have been reclassified to conform to the current presentation. The recognition of excess tax benefits related to share-based payments resulted in a reclassification from Deferred income taxes to Retained earnings in the Consolidated Balance Sheet for the year ended December 31, 2016. See further detail in the new accounting pronouncements discussion. FAIR VALUE — Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly, hypothetical transaction between market participants at the measurement date, or exit price. The Company applies the fair value measurement accounting guidance to financial assets and liabilities in determining the fair value of investments in marketable debt and equity securities, included in the Consolidated Balance Sheet line items Short-term investments and Other assets (noncurrent) ; derivative assets, included in Other current assets and Other assets (noncurrent) ; and, derivative liabilities, included in Accrued and other liabilities (current) and Other long-term liabilities . The Company applies the fair value measurement guidance to nonfinancial assets and liabilities upon the acquisition of a business or in conjunction with the measurement of an asset retirement obligation or a potential impairment loss on an asset group or goodwill. When determining the fair value measurements for assets and liabilities required to be reflected at their fair values, the Company considers the principal or most advantageous market in which it would transact and considers assumptions that market participants would use when pricing the assets or liabilities, such as inherent risk, transfer restrictions and risk of nonperformance. The Company is prohibited from including transaction costs and any adjustments for blockage factors in determining fair value. In determining fair value measurements, the Company maximizes the use of observable inputs and minimizes the use of unobservable inputs. Assets and liabilities are categorized within a fair value hierarchy based upon the lowest level of input that is significant to the fair value measurement: • Level 1: Quoted prices in active markets for identical assets or liabilities • Level 2: Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices in active markets for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; or • Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair values of the assets or liabilities Any transfers between all levels within the fair value hierarchy levels are recognized at the end of the reporting period. CASH AND CASH EQUIVALENTS — The Company considers unrestricted cash on hand, cash balances not restricted as to withdrawal or usage, deposits in banks, certificates of deposit and short-term marketable securities with original maturities of three months or less to be cash and cash equivalents. RESTRICTED CASH AND DEBT SERVICE RESERVES — Cash balances restricted as to withdrawal or usage, primarily via contract, are considered restricted cash. INVESTMENTS IN MARKETABLE SECURITIES — The Company's marketable investments are primarily unsecured debentures, certificates of deposit, government debt securities and money market funds. Short-term investments consist of marketable equity securities and debt securities with original maturities in excess of three months with remaining maturities of less than one year. Marketable debt securities where the Company has both the positive intent and ability to hold to maturity are classified as held-to-maturity and are carried at amortized cost. Remaining marketable securities are classified as available-for-sale or trading and are carried at fair value. Available-for-sale and trading investment's unrealized gains or losses are reflected in AOCL, a separate component of equity, and the Consolidated Statements of Operations, respectively .. Interest and dividends on investments are reported in interest income and other income , respectively. Gains and losses on sales of investments are determined using the specific identification method. ACCOUNTS AND NOTES RECEIVABLE AND ALLOWANCE FOR DOUBTFUL ACCOUNTS — Accounts and notes receivable are carried at amortized cost. The Company periodically assesses the collectability of accounts receivable, considering factors such as historical collection experience, the age of accounts receivable and other currently available evidence supporting collectability, and records an allowance for doubtful accounts for the estimated uncollectible amount as appropriate. Certain of our businesses charge interest on accounts receivable. Interest income is recognized on an accrual basis. When collection of such interest is not reasonably assured, interest income is recognized as cash is received. Individual accounts and notes receivable are written off when they are no longer deemed collectible. INVENTORY — Inventory primarily consists of fuel and other raw materials used to generate power, and operational spare parts and supplies used to maintain power generation and distribution facilities. Inventory is carried at lower of cost or net realizable value. Cost is the sum of the purchase price and expenditures incurred to bring the inventory to its existing location. Inventory is primarily valued using the average cost method. Generally, if it is expected fuel inventory will not be recovered through revenue earned from power generation, an impairment is recognized to reflect the fuel at market value. The carrying amount of spare parts and supplies is typically reduced only in instances where the items are considered obsolete. LONG-LIVED ASSETS — Long-lived assets include property, plant and equipment, assets under capital leases and intangible assets subject to amortization (i.e., finite-lived intangible assets). Property, plant and equipment — Property, plant and equipment are stated at cost, net of accumulated depreciation. The cost of renewals and improvements that extend the useful life of property, plant and equipment are capitalized. Construction progress payments, engineering costs, insurance costs, salaries, interest and other costs directly relating to construction in progress are capitalized during the construction period, provided the completion of the construction project is deemed probable, or expensed at the time construction completion is determined to no longer be probable. The continued capitalization of such costs is subject to risks related to successful completion, including those related to government approvals, site identification, financing, construction permitting and contract compliance. Construction-in-progress balances are transferred to electric generation and distribution assets when an asset group is ready for its intended use. Government subsidies, liquidated damages recovered for construction delays, and income tax credits are recorded as a reduction to property, plant and equipment and reflected in cash flows from investing activities. Maintenance and repairs are charged to expense as incurred. Depreciation, after consideration of salvage value and asset retirement obligations, is computed using the straight-line method over the estimated useful lives of the assets, which are determined on a composite or component basis. Capital spare parts, including rotable spare parts, are included in electric generation and distribution assets. If the spare part is considered a component, it is depreciated over its useful life after the part is placed in service. If the spare part is deemed part of a composite asset, the part is depreciated over the composite useful life even when being held as a spare part. The Company's Brazilian subsidiaries operate under concession contracts. Certain estimates are utilized to determine depreciation expense for the Brazilian subsidiaries, including the useful lives of the property, plant and equipment and the amounts to be recovered at the end of the concession contract. The amounts to be recovered under these concession contracts are based on estimates that are inherently uncertain and actual amounts recovered may differ from those estimates. These concession contracts are not within the scope of ASC 853— Service Concession Arrangements . Intangible Assets Subject to Amortization — Finite-lived intangible assets are amortized over their useful lives which range from 3 – 50 years. The Company accounts for purchased emission allowances as intangible assets and records an expense when they are utilized or sold. Granted emission allowances are valued at zero. Impairment of Long-lived Assets — When circumstances indicate the carrying amount of long-lived assets in a held-for-use asset group may not be recoverable, the Company evaluates the assets for potential impairment using internal projections of undiscounted cash flows resulting from the use and eventual disposal of the assets. Events or changes in circumstances that may necessitate a recoverability evaluation include, but are not limited to, adverse changes in the regulatory environment, unfavorable changes in power prices or fuel costs, increased competition due to additional capacity in the grid, technological advancements, declining trends in demand, or an expectation it is more likely than not that the asset will be disposed of before the end of its previously estimated useful life. If the carrying amount of the assets exceeds the undiscounted cash flows, an impairment expense is recognized for the amount by which the carrying amount of the asset group exceeds its fair value (subject to the carrying amount not being reduced below fair value for any individual long-lived asset that is determinable without undue cost and effort). An impairment expense for certain assets may be reduced by the establishment of a regulatory asset if recovery through approved rates is probable. SERVICE CONCESSION ASSETS — Service concession assets are stated at cost, net of accumulated amortization, in accordance with ASC 853. Service concession assets represent the cost of all infrastructure to be transferred to the public-sector entity grantors at the end of the concession. These costs primarily represent construction progress payments, engineering costs, insurance costs, salaries, interest and other costs directly relating to construction of the service concession infrastructure. Government subsidies, liquidated damages recovered for construction delays and income tax credits are recorded as a reduction to Service Concession Assets. Service concession assets are amortized and recognized in earnings as a cost of goods sold as infrastructure construction revenue is recognized. Services provided under concession arrangements are recognized on a straight line basis. DEBT ISSUANCE COSTS — Costs incurred in connection with the issuance of long-term debt are deferred and presented as a direct reduction from the face amount of that debt and amortized over the related financing period using the effective interest method. Debt issuance costs related to a line-of-credit or revolving credit facility are deferred and presented as an asset and amortized over the related financing period. Make-whole payments in connection with early debt retirements are classified as cash flows used in financing activities. GOODWILL AND INDEFINITE-LIVED INTANGIBLE ASSETS — The Company evaluates goodwill and indefinite-lived intangible assets for impairment on an annual basis and whenever events or changes in circumstances necessitate an evaluation for impairment. The Company's annual impairment testing date is October first. Goodwill — Goodwill represents the excess of the purchase price of the business acquisition over the fair value of identifiable net assets acquired. Goodwill resulting from an acquisition is assigned to the reporting units that are expected to benefit from the synergies of the acquisition. Generally, each AES business with a goodwill balance constitutes a reporting unit as they are not similar to other businesses in a segment nor are they reported to segment management together with other businesses. Goodwill is evaluated for impairment either under the qualitative assessment option or the two-step quantitative test. If goodwill is determined to be impaired, the fair value of individual assets and liabilities is determined to compute the implied fair value of goodwill. If the carrying amount of goodwill exceeds its implied fair value, the excess is recognized as an impairment loss up to the carrying amount of the goodwill. Indefinite-Lived Intangible Assets — The Company's indefinite-lived intangible assets primarily include land-use rights and water rights. Indefinite-lived Intangible Assets are evaluated for impairment either under the qualitative assessment option or the two-step quantitative test. If the carrying amount of an intangible asset being tested for impairment exceeds its fair value, the excess is recognized as impairment expense. ACCOUNTS PAYABLE AND OTHER ACCRUED LIABILITIES — Accounts payable consists of amounts due to trade creditors related to the Company's core business operations. These payables include amounts owed to vendors and suppliers for items such as energy purchased for resale, fuel, maintenance, inventory and other raw materials. Other accrued liabilities include items such as income taxes, regulatory liabilities, legal contingencies and employee-related costs, including payroll, benefits and related taxes. REGULATORY ASSETS AND LIABILITIES — The Company recognizes assets and liabilities that result from regulated ratemaking processes. Regulatory assets generally represent incurred costs which have been deferred due to the probable future recovery via customer rates. Generally, returns earned on regulatory assets are reflected in the Consolidated Statement of Operations within Interest Income . Regulatory liabilities generally represent obligations to refund customers. Management continually assesses whether regulatory assets are probable of future recovery and regulatory liabilities are probable of future payment by considering factors such as applicable regulatory changes, recent rate orders applicable to other regulated entities, and the status of any pending or potential deregulation legislation. If future recovery of costs previously deferred ceases to be probable, the related regulatory assets are written off and recognized in income from continuing operations. PENSION AND OTHER POSTRETIREMENT PLANS — The Company recognizes in its Consolidated Balance Sheets an asset or liability reflecting the funded status of pension and other postretirement plans with current-year changes in actuarial gains or losses recognized in AOCL, except for those plans at certain of the Company's regulated utilities that can recover portions of their pension and postretirement obligations through future rates. All plan assets are recorded at fair value. AES follows the measurement date provisions of the accounting guidance, which require a year-end measurement date of plan assets and obligations for all defined benefit plans. INCOME TAXES — Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of the existing assets and liabilities, and their respective income tax bases. The Company establishes a valuation allowance when it is more likely than not that all or a portion of a deferred tax asset will not be realized. The Company's tax positions are evaluated under a more likely than not recognition threshold and measurement analysis before they are recognized for financial statement reporting. Uncertain tax positions have been classified as noncurrent income tax liabilities unless expected to be paid within one year. The Company's policy for interest and penalties related to income tax exposures is to recognize interest and penalties as a component of the provision for income taxes in the Consolidated Statements of Operations. The Company has not yet determined its accounting policy election, as outlined by SAB 118, with respect to the new GILTI provisions of U.S. tax reform, applicable from January 1, 2018. See Note 20 — Income Taxes for additional discussion regarding the U.S. tax reform. ASSET RETIREMENT OBLIGATIONS — The Company records the fair value of a liability for a legal obligation to retire an asset in the period in which the obligation is incurred. When a new liability is recognized, the Company capitalizes the costs of the liability by increasing the carrying amount of the related long-lived asset. The liability is accreted to its present value each period and the capitalized cost is depreciated over the useful life of the related asset. Upon settlement of the obligation, the Company eliminates the liability and, based on the actual cost to retire, may incur a gain or loss. FOREIGN CURRENCY TRANSLATION — A business's functional currency is the currency of the primary economic environment in which the business operates and is generally the currency in which the business generates and expends cash. Subsidiaries and affiliates whose functional currency is a currency other than the U.S. dollar translate their assets and liabilities into U.S. dollars at the current exchange rates in effect at the end of the fiscal period. Adjustments arising from the translation of the balance sheet of such subsidiaries are included in AOCL. The revenue and expense accounts of such subsidiaries and affiliates are translated into U.S. dollars at the average exchange rates for the period. Gains and losses on intercompany foreign currency transactions that are long-term in nature and which the Company does not intend to settle in the foreseeable future, are also recognized in AOCL. Gains and losses that arise from exchange rate fluctuations on transactions denominated in a currency other than the functional currency are included in determining net income. Accumulated foreign currency translation adjustments are reclassified from AOCL to net income only when realized upon sale or upon complete or substantially complete liquidation of the investment in a foreign entity. The accumulated adjustments are included in carrying amounts in impairment assessments where the Company has committed to a plan that will cause the accumulated adjustments to be reclassified to earnings. REVENUE RECOGNITION — Revenue from utilities is classified as regulated in the Consolidated Statements of Operations. Revenue from the sale of energy is recognized in the period during which the sale occurs. The calculation of revenue earned but not yet billed is based on the number of days not billed in the month, the estimated amount of energy delivered during those days and the estimated average price per customer class for that month. Differences between actual and estimated unbilled revenue are usually immaterial. The Company has businesses where it sells and purchases power to and from ISOs and RTOs. In those instances, the Company accounts for these transactions on a net hourly basis because the transactions are settled on a net hourly basis. Revenue from generation businesses is classified as non-regulated in the Consolidated Statements of Operations. Revenue is recognized based upon output delivered and capacity provided, at rates as specified under contract terms or prevailing market rates. Certain of the Company's PPAs meet the definition of an operating lease or contain similar arrangements. Typically, minimum lease payments from such PPAs are recognized as revenue on a straight-line basis over the lease term whereas contingent rentals are recognized when earned. Revenue is recorded net of any taxes assessed on and collected from customers, which are remitted to the governmental authorities. SHARE-BASED COMPENSATION — The Company grants share-based compensation in the form of stock options, restricted stock units, performance stock units, and performance cash units. The expense is based on the grant-date fair value of the equity or liability instrument issued and is recognized on a straight-line basis over the requisite service period, net of estimated forfeitures. The Company uses a Black-Scholes option pricing model to estimate the fair value of stock options granted to its employees. GENERAL AND ADMINISTRATIVE EXPENSES — General and administrative expenses include corporate and other expenses related to corporate staff functions and initiatives, primarily executive management, finance, legal, human resources and information systems, which are not directly allocable to our business segments. Additionally, all costs associated with corporate business development efforts are classified as general and administrative expenses. DERIVATIVES AND HEDGING ACTIVITIES — Under the accounting standards for derivatives and hedging, the Company recognizes all contracts that meet the definition of a derivative, except those designated as normal purchase or normal sale at inception, as either assets or liabilities in the Consolidated Balance Sheets and measures those instruments at fair value. See the Company's fair value policy and Note 4— Fair Value and Fair value in this section for additional discussion regarding the determination of fair value. PPAs and fuel supply agreements are evaluated to assess if they contain either a derivative or an embedded derivative requiring separate valuation and accounting. Generally, these agreements do not meet the definition of a derivative, often due to the inability to be net

Inventory

Inventory	12 Months Ended
	Dec. 31, 2017
Inventory Disclosure [Abstract]
INVENTORY	INVENTORY Inventory is valued primarily using the average-cost method. The following table summarizes the Company's inventory balances as of the dates indicated (in millions): December 31, 2017 2016 Fuel and other raw materials $ 284 $ 302 Spare parts and supplies 278 320 Total $ 562 $ 622

Property Plant and Equipment

Property Plant and Equipment	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT	PROPERTY, PLANT AND EQUIPMENT The following table summarizes the components of the electric generation and distribution assets and other property, plant and equipment (in millions) with their estimated useful lives (in years). The amounts are stated net of all prior asset impairment losses recognized. December 31, Estimated Useful Life 2017 2016 Electric generation and distribution facilities 8 - 40 $ 21,529 $ 22,337 Other buildings 5 - 71 1,971 1,906 Furniture, fixtures and equipment 2 - 32 284 303 Other 5 - 44 335 365 Total electric generation and distribution assets and other 24,119 24,911 Accumulated depreciation (7,942 ) (7,919 ) Net electric generation and distribution assets and other $ 16,177 $ 16,992 The following table summarizes depreciation expense (including the amortization of assets recorded under capital leases and the amortization of asset retirement obligations) and interest capitalized during development and construction on qualifying assets for the periods indicated (in millions): Years Ended December 31, 2017 2016 2015 Depreciation expense $ 1,005 $ 1,002 $ 958 Interest capitalized during development and construction 139 118 84 Property, plant and equipment, net of accumulated depreciation, of $10 billion was mortgaged, pledged or subject to liens as of December 31, 2017 and 2016 , including assets classified as held-for-sale. The following table summarizes regulated and non-regulated generation and distribution property, plant and equipment and accumulated depreciation as of the dates indicated (in millions): December 31, 2017 2016 Regulated generation, distribution assets and other, gross $ 8,093 $ 7,815 Regulated accumulated depreciation (3,357 ) (3,299 ) Regulated generation, distribution assets and other, net 4,736 4,516 Non-regulated generation, distribution assets and other, gross 16,026 17,096 Non-regulated accumulated depreciation (4,585 ) (4,620 ) Non-regulated generation, distribution assets and other, net 11,441 12,476 Net electric generation, distribution assets and other $ 16,177 $ 16,992 The following table presents amounts recognized related to asset retirement obligations for the periods indicated (in millions): 2017 2016 Balance at January 1 $ 357 $ 247 Additional liabilities incurred 1 12 Liabilities settled (21 ) (4 ) Accretion expense 16 15 Change in estimated cash flows 25 86 Other (10 ) 1 Balance at December 31 $ 368 $ 357 The Company's asset retirement obligations primarily include active ash landfills, water treatment basins and the removal or dismantlement of certain plants and equipment. The $25 million increase in estimated cash flows for 2017 is primarily related to the legal obligations for the demolition of the Huntington Beach Units in connection with the Southland re-powering project.

Fair Value

Fair Value	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
FAIR VALUE	FAIR VALUE The fair value of current financial assets and liabilities, debt service reserves and other deposits approximate their reported carrying amounts. The estimated fair values of the Company's assets and liabilities have been determined using available market information. By virtue of these amounts being estimates and based on hypothetical transactions to sell assets or transfer liabilities, the use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. Valuation Techniques — The fair value measurement accounting guidance describes three main approaches to measuring the fair value of assets and liabilities: (1) market approach, (2) income approach and (3) cost approach. The market approach uses prices and other relevant information generated from market transactions involving identical or comparable assets or liabilities. The income approach uses valuation techniques to convert future amounts to a single present value amount. The measurement is based on current market expectations of the return on those future amounts. The cost approach is based on the amount that would currently be required to replace an asset. The Company measures its investments and derivatives at fair value on a recurring basis. Additionally, in connection with annual or event-driven impairment evaluations, certain nonfinancial assets and liabilities are measured at fair value on a nonrecurring basis. These include long-lived tangible assets (i.e., property, plant and equipment), goodwill and intangible assets (e.g., sales concessions, land use rights and water rights, etc.). In general, the Company determines the fair value of investments and derivatives using the market approach and the income approach, respectively. In the nonrecurring measurements of nonfinancial assets and liabilities, all three approaches are considered; however, the value estimated under the income approach is often the most representative of fair value. Investments — The Company's investments measured at fair value generally consist of marketable debt and equity securities. Equity securities are either measured at fair value using quoted market prices or based on comparisons to market data obtained for similar assets. Debt securities primarily consist of unsecured debentures and certificates of deposit held by our Brazilian subsidiaries. Returns and pricing on these instruments are generally indexed to the market interest rates in Brazil. Debt securities are measured at fair value based on comparisons to market data obtained for similar assets. Derivatives — Derivatives are measured at fair value using quoted market prices or the income approach utilizing volatilities, spot and forward benchmark interest rates (such as LIBOR and EURIBOR), foreign exchange rates, credit data, and commodity prices, as applicable. When significant inputs are not observable, the Company uses relevant techniques to determine the inputs, such as regression analysis or prices for similarly traded instruments available in the market. The Company's methodology to fair value its derivatives is to start with any observable inputs; however, in certain instances the published forward rates or prices may not extend through the remaining term of the contract and management must make assumptions to extrapolate the curve, which necessitates the use of unobservable inputs, such as proxy commodity prices or historical settlements to forecast forward prices. Specifically, where there is limited forward curve data with respect to foreign exchange contracts, beyond the traded points, the Company utilizes the interest rate differential approach to construct the remaining portion of the forward curve. Similarly, in certain instances, the spread that reflects the credit or nonperformance risk is unobservable requiring the use of proxy yield curves of similar credit quality. To determine the fair value of a derivative, cash flows are discounted using the relevant spot benchmark interest rate. The Company then makes a credit valuation adjustment ("CVA"), as applicable, by further discounting the cash flows for nonperformance or credit risk based on the observable or estimated debt spread of the Company's subsidiary or its counterparty and the tenor of the respective derivative instrument. The CVA for potential future scenarios in which the derivative is in an asset position is based on the counterparty's credit ratings, credit default swap spreads, and debt spreads, as available. The CVA for potential future scenarios in which the derivative is in a liability position is based on the Parent Company's or the subsidiary's current debt spread. In the absence of readily obtainable credit information, the Parent Company's or the subsidiary's estimated credit rating (based on applying a standard industry model to historical financial information and then considering other relevant information) and spreads of comparably rated entities or the respective country's debt spreads are used as a proxy. All derivative instruments are analyzed individually and are subject to unique risk exposures. The fair value hierarchy of an asset or a liability is based on the level of significance of the input assumptions. An input assumption is considered significant if it affects the fair value by at least 10%. Assets and liabilities are classified as Level 3 when the use of unobservable inputs is significant. When the use of unobservable inputs is insignificant, assets and liabilities are classified as Level 2. Transfers between Level 3 and Level 2 are determined as of the end of the reporting period and result from changes in significance of unobservable inputs used to calculate the CVA. Debt — Recourse and non-recourse debt are carried at amortized cost. The fair value of recourse debt is estimated based on quoted market prices. The fair value of non-recourse debt is estimated based upon interest rates and other features of the loan. In general, the carrying amount of variable rate debt is a close approximation of its fair value. For fixed rate loans, the fair value is estimated using quoted market prices or discounted cash flow ("DCF") analyses. The fair value of recourse and non-recourse debt excludes accrued interest at the valuation date. The fair value was determined using available market information as of December 31, 2017 . The Company is not aware of any factors that would significantly affect the fair value amounts subsequent to December 31, 2017 . Nonrecurring measurements — For nonrecurring measurements derived using the income approach, fair value is generally determined using valuation models based on the principles of DCF. The income approach is most often used in the impairment evaluation of long-lived tangible assets, equity method investments, goodwill, and intangible assets. Where the use of market observable data is limited or not available for certain input assumptions, the Company develops its own estimates using a variety of techniques such as regression analysis and extrapolations. Depending on the complexity of a valuation, an independent valuation firm may be engaged to assist management in the valuation process. For nonrecurring measurements derived using the market approach, recent market transactions involving the sale of identical or similar assets are considered. The use of this approach is limited because it is often difficult to identify sale transactions of identical or similar assets. This approach is used in impairment evaluations of certain intangible assets. Otherwise, it is used to corroborate the fair value determined under the income approach. For nonrecurring measurements derived using the cost approach, fair value is typically based upon a replacement cost approach. This approach involves a considerable amount of judgment, which is why its use is limited to the measurement of long-lived tangible assets. Like the market approach, this approach is also used to corroborate the fair value determined under the income approach. Fair Value Considerations — In determining fair value, the Company considers the source of observable market data inputs, liquidity of the instrument, the credit risk of the counterparty and the risk of the Company's or its counterparty's nonperformance. The conditions and criteria used to assess these factors are: Sources of market assumptions — The Company derives most of its market assumptions from market efficient data sources (e.g., Bloomberg and Reuters). To determine fair value, where market data is not readily available, management uses comparable market sources and empirical evidence to develop its own estimates of market assumptions. Market liquidity — The Company evaluates market liquidity based on whether the financial or physical instrument, or the underlying asset, is traded in an active or inactive market. An active market exists if the prices are fully transparent to market participants, can be measured by market bid and ask quotes, the market has a relatively large proportion of trading volume as compared to the Company's current trading volume and the market has a significant number of market participants that will allow the market to rapidly absorb the quantity of assets traded without significantly affecting the market price. Another factor the Company considers when determining whether a market is active or inactive is the presence of government or regulatory controls over pricing that could make it difficult to establish a market-based price when entering into a transaction. Nonperformance risk — Nonperformance risk refers to the risk that an obligation will not be fulfilled and affects the value at which a liability is transferred or an asset is sold. Nonperformance risk includes, but may not be limited to, the Company or its counterparty's credit and settlement risk. Nonperformance risk adjustments are dependent on credit spreads, letters of credit, collateral, other arrangements available and the nature of master netting arrangements. The Company is party to various interest rate swaps and options; foreign currency options and forwards; and derivatives and embedded derivatives, which subject the Company to nonperformance risk. The financial and physical instruments held at the subsidiary level are generally non-recourse to the Parent Company. Nonperformance risk on the investments held by the Company is incorporated in the fair value derived from quoted market data to mark the investments to fair value. Recurring Measurements — The following table presents, by level within the fair value hierarchy, as described in Note 1— General and Summary of Significant Accounting Policies , the Company's financial assets and liabilities that were measured at fair value on a recurring basis as of the dates indicated (in millions). For the Company's investments in marketable debt and equity securities, the security classes presented are determined based on the nature and risk of the security and are consistent with how the Company manages, monitors and measures its marketable securities: December 31, 2017 December 31, 2016 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets AVAILABLE FOR SALE: Debt securities: Unsecured debentures $ — $ 207 $ — $ 207 $ — $ 205 $ — $ 205 Certificates of deposit — 153 — 153 — 260 — 260 Government debt securities — — — — — 9 — 9 Subtotal — 360 — 360 — 474 — 474 Equity securities: Mutual funds — 52 — 52 — 48 — 48 Subtotal — 52 — 52 — 48 — 48 Total available for sale — 412 — 412 — 522 — 522 TRADING: Equity securities: Mutual funds 20 — — 20 16 — — 16 Total trading 20 — — 20 16 — — 16 DERIVATIVES: Interest rate derivatives — 15 — 15 — 18 — 18 Cross-currency derivatives — 29 — 29 — 4 — 4 Foreign currency derivatives — 29 240 269 — 54 255 309 Commodity derivatives — 30 5 35 — 38 7 45 Total derivatives — assets — 103 245 348 — 114 262 376 TOTAL ASSETS $ 20 $ 515 $ 245 $ 780 $ 16 $ 636 $ 262 $ 914 Liabilities DERIVATIVES: Interest rate derivatives $ — $ 111 $ 151 $ 262 $ — $ 121 $ 179 $ 300 Cross-currency derivatives — 3 — 3 — 18 — 18 Foreign currency derivatives — 30 — 30 — 64 — 64 Commodity derivatives — 19 1 20 — 40 2 42 Total derivatives — liabilities — 163 152 315 — 243 181 424 TOTAL LIABILITIES $ — $ 163 $ 152 $ 315 $ — $ 243 $ 181 $ 424 As of December 31, 2017 , all AFS debt securities had stated maturities within one year. For the years ended December 31, 2017 , 2016 , and 2015 , no other-than-temporary impairment of marketable securities were recognized in earnings or Other Comprehensive Income (Loss). Gains and losses on the sale of investments are determined using the specific-identification method. The following table presents gross proceeds from sale of AFS securities for the periods indicated (in millions): Year Ended December 31, 2017 2016 2015 Gross proceeds from sales of AFS securities $ 1,398 $ 1,726 $ 1,226 Any Level 1 derivative instruments are exchange-traded commodity futures for which the pricing is observable in active markets, and as such, these are not expected to transfer to other levels. There have been no transfers between Level 1 and Level 2. The following tables present a reconciliation of net derivative assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the years ended December 31, 2017 and 2016 (presented net by type of derivative in millions). Transfers between Level 3 and Level 2 are determined as of the end of the reporting period and principally result from changes in the significance of unobservable inputs used to calculate the credit valuation adjustment. Year Ended December 31, 2017 Interest Rate Foreign Currency Commodity Total Balance at January 1 $ (179 ) $ 255 $ 5 $ 81 Total realized and unrealized gains (losses): Included in earnings (1 ) 21 1 21 Included in other comprehensive income — derivative activity (23 ) — — (23 ) Included in regulatory liabilities — — 10 10 Settlements 36 (36 ) (12 ) (12 ) Transfers of liabilities into Level 3 (4 ) — — (4 ) Transfers of liabilities out of Level 3 20 — — 20 Balance at December 31 $ (151 ) $ 240 $ 4 $ 93 Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities held at the end of the period $ 7 $ (15 ) $ 1 $ (7 ) Year Ended December 31, 2016 Interest Rate Foreign Currency Commodity Total Balance at January 1 $ (304 ) $ 277 $ 3 $ (24 ) Total realized and unrealized gains (losses): Included in earnings — 31 2 33 Included in other comprehensive income — derivative activity (36 ) 6 — (30 ) Included in other comprehensive income — foreign currency translation activity 3 (52 ) — (49 ) Included in regulatory liabilities — — 11 11 Settlements 72 (22 ) (11 ) 39 Transfers of liabilities into Level 3 (32 ) — — (32 ) Transfers of assets out of Level 3 118 15 — 133 Balance at December 31 $ (179 ) $ 255 $ 5 $ 81 Total gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities held at the end of the period $ 6 $ 16 $ 2 $ 24 The following table summarizes the significant unobservable inputs used for the Level 3 derivative assets (liabilities) as of December 31, 2017 (in millions, except range amounts): Type of Derivative Fair Value Unobservable Input Amount or Range (Weighted Average) Interest rate $ (151 ) Subsidiaries’ credit spreads 1.9% - 5.1% (4.9%) Foreign currency: Argentine peso 240 Argentine peso to U.S. dollar currency exchange rate after one year (1) 22.8 - 52.3 (36.6) Commodity: Other 4 Total $ 93 ____________________________ (1) During the year ended December 31, 2017 , the Company began utilizing the interest rate differential approach to construct the remaining portion of the forward curve after one year (beyond the traded points). In previous periods, the Company used the purchasing price parity approach to construct the forward curve. For interest rate derivatives, and foreign currency derivatives, increases (decreases) in the estimates of the Company's own credit spreads would decrease (increase) the value of the derivatives in a liability position. For foreign currency derivatives, increases (decreases) in the estimate of the above exchange rate would increase (decrease) the value of the derivative. Nonrecurring Measurements When evaluating impairment of long-lived assets and equity method investments, the Company measures fair value using the applicable fair value measurement guidance. Impairment expense is measured by comparing the fair value at the evaluation date to their then-latest available carrying amount. The following table summarizes major categories of assets and liabilities measured at fair value on a nonrecurring basis during the period and their level within the fair value hierarchy (in millions): Year Ended December 31, 2017 Measurement Date Carrying Amount (1) Fair Value Pre-tax Loss Assets Level 1 Level 2 Level 3 Long-lived assets held and used: (2) Laurel Mountain 12/31/2017 $ 154 $ — $ — $ 33 $ 121 Kilroot 12/31/2017 69 — — 20 37 DPL 02/28/2017 77 — — 11 66 Other Various 18 — — — 18 Dispositions and held-for-sale businesses: (3) DPL Peaker Assets 12/31/2017 346 — 237 — 109 Kazakhstan Hydroelectric (4) 06/30/2017 190 — 92 — 92 Kazakhstan CHPs 03/31/2017 171 — 29 — 94 Year Ended December 31, 2016 Measurement Date Carrying Amount (1) Fair Value Pre-tax Loss Assets Level 1 Level 2 Level 3 Long-lived assets held and used: (2) DPL 12/31/2016 $ 787 $ — $ 60 $ 103 $ 624 Buffalo Gap I 08/31/2016 113 — — 36 77 DPL 06/30/2016 324 — — 89 235 Buffalo Gap II 03/31/2016 251 — — 92 159 Discontinued operations: (3) Sul 06/30/2016 1,581 — 470 — 783 _____________________________ (1) Represents the carrying values at the dates of measurement, before fair value adjustment. (2) See Note 19 — Asset Impairment Expense for further information. (3) Per the Company's policy, pre-tax loss is limited to the impairment of long-lived assets. Any additional loss will be recognized on completion of the sale. Upon disposal of Sul, we incurred an additional pre-tax loss on sale of $602 million . See Note 21 — Discontinued Operations and Note 22 — Held-for-Sale Businesses and Dispositions for further information. (4) Per the Company's policy, pre-tax loss is limited to the impairment of long-lived assets. Any additional loss will be recognized on completion of the sale. Upon disposal of Kazakhstan HPPs, we incurred an additional pre-tax loss on disposal of $33 million . See Note 19 — Asset Impairment Expense and Note 22 — Held-for-Sale Businesses and Dispositions for further information. The following table summarizes the significant unobservable inputs used in the Level 3 measurement of long-lived assets held and used measured on a nonrecurring basis during the year ended December 31, 2017 (in millions, except range amounts): December 31, 2017 Fair Value Valuation Technique Unobservable Input Range (Weighted Average) Long-lived assets held and used: Laurel Mountain $ 33 Discounted cash flow Annual revenue growth -30% to 2% (0%) Pre-tax operating margin (through remaining life) 61% to 73% (64%) Weighted-average cost of capital 9% Kilroot 20 Discounted cash flow Annual revenue growth -85% to 17% (-16%) Annual pre-tax operating margin -32% to 28% (6%) Weighted-average cost of capital 8% DPL 11 Discounted cash flow Pre-tax operating margin (through remaining life) 10% to 22% (15%) Weighted-average cost of capital 7% Total $ 64 Financial Instruments not Measured at Fair Value in the Consolidated Balance Sheets The following table presents (in millions) the carrying amount, fair value and fair value hierarchy of the Company's financial assets and liabilities that are not measured at fair value in the Consolidated Balance Sheets as of the periods indicated, but for which fair value is disclosed. December 31, 2017 Carrying Amount Fair Value Total Level 1 Level 2 Level 3 Assets: Accounts receivable — noncurrent (1) $ 163 $ 217 $ — $ 6 $ 211 Liabilities: Non-recourse debt 15,340 15,890 — 13,350 2,540 Recourse debt 4,630 4,920 — 4,920 — December 31, 2016 Carrying Amount Fair Value Total Level 1 Level 2 Level 3 Assets: Accounts receivable — noncurrent (1) $ 232 $ 342 $ — $ 20 $ 322 Liabilities: Non-recourse debt 14,783 15,185 — 14,140 1,045 Recourse debt 4,671 4,899 — 4,899 — _____________________________ (1) These amounts primarily relate to amounts due from CAMMESA, the administrator of the wholesale electricity market in Argentina, and are included in Other noncurrent assets in the accompanying Consolidated Balance Sheets. The fair value and carrying amount of these receivables exclude VAT of $31 million and $24 million as of December 31, 2017 and 2016 , respectively.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES	DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES Volume of Activity — The following table presents the Company's maximum notional (in millions) over the remaining contractual period by type of derivative as of December 31, 2017 , regardless of whether they are in qualifying cash flow hedging relationships, and the dates through which the maturities for each type of derivative range: Derivatives Maximum Notional Translated to USD Latest Maturity Interest Rate (LIBOR and EURIBOR) $ 4,481 2036 Cross-Currency Swaps (Chilean Unidad de Fomento and Chilean Peso) 410 2029 Foreign Currency: Argentine Peso 187 2026 Chilean Peso 410 2020 Colombian Peso 305 2019 Others, primarily with weighted average remaining maturities of a year or less 303 2020 Accounting and Reporting — Assets and Liabilities — The following tables present the fair value of assets and liabilities related to the Company's derivative instruments as of the periods indicated (in millions): Fair Value December 31, 2017 December 31, 2016 Assets Designated Not Designated Total Designated Not Designated Total Interest rate derivatives $ 15 $ — $ 15 $ 18 $ — $ 18 Cross-currency derivatives 29 — 29 4 — 4 Foreign currency derivatives 8 261 269 9 300 309 Commodity derivatives 5 30 35 20 25 45 Total assets $ 57 $ 291 $ 348 $ 51 $ 325 $ 376 Liabilities Interest rate derivatives $ 125 $ 137 $ 262 $ 295 $ 5 $ 300 Cross-currency derivatives 3 — 3 18 — 18 Foreign currency derivatives 1 29 30 19 45 64 Commodity derivatives 9 11 20 26 16 42 Total liabilities $ 138 $ 177 $ 315 $ 358 $ 66 $ 424 December 31, 2017 December 31, 2016 Fair Value Assets Liabilities Assets Liabilities Current $ 84 $ 211 $ 99 $ 155 Noncurrent 264 104 277 269 Total $ 348 $ 315 $ 376 $ 424 Credit Risk-Related Contingent Features (1) December 31, 2017 December 31, 2016 Present value of liabilities subject to collateralization $ 15 $ 41 Cash collateral held by third parties or in escrow 9 18 _____________________________ (1) Based on the credit rating of certain subsidiaries Earnings and Other Comprehensive Income (Loss) — The following table presents (in millions) the pre-tax gains (losses) recognized in AOCL and earnings related to all derivative instruments for the periods indicated: Years Ended December 31, 2017 2016 2015 Effective portion of cash flow hedges Gains (losses) recognized in AOCL Interest rate derivatives $ (66 ) $ (35 ) $ (103 ) Cross-currency derivatives 31 21 (20 ) Foreign currency derivatives (5 ) (4 ) 10 Commodity derivatives 18 30 40 Total $ (22 ) $ 12 $ (73 ) Gains (losses) reclassified from AOCL to earnings Interest rate derivatives $ (82 ) $ (101 ) $ (116 ) Cross-currency derivatives 34 8 (24 ) Foreign currency derivatives (20 ) (8 ) 32 Commodity derivatives 17 56 31 Total $ (51 ) $ (45 ) $ (77 ) Loss reclassified from AOCL to earnings due to discontinuance of hedge accounting (1) $ (13 ) $ — $ — Gain (losses) recognized in earnings related to Ineffective portion of cash flow hedges $ 3 $ (1 ) $ (6 ) Not designated as hedging instruments: Foreign currency derivatives $ 1 $ 19 $ 211 Commodity derivatives and other 14 (16 ) (29 ) Total $ 15 $ 3 $ 182 _____________________________ (1) Cash flow hedge was discontinued because it was probable the forecasted transaction will not occur. The AOCL expected to decrease pre-tax income from continuing operations, primarily due to interest rate derivatives, for the twelve months ended December 31, 2017 is $58 million .

Financing Receivables

Financing Receivables	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
FINANCING RECEIVABLES	FINANCING RECEIVABLES Receivables with contractual maturities of greater than one year are considered financing receivables, primarily related to amended agreements or government resolutions due from CAMMESA. The following table presents financing receivables by country as of the dates indicated (in millions): December 31, 2017 2016 Argentina $ 177 $ 236 Other 17 20 Total $ 194 $ 256 Argentina Collection of the principal and interest on these receivables is subject to various business risks and uncertainties, including, but not limited to, the continued operation of power plants which generate cash for payments of these receivables, regulatory changes that could impact the timing and amount of collections, and economic conditions in Argentina. The Company monitors these risks, including the credit ratings of the Argentine government, on a quarterly basis to assess the collectability of these receivables. The Company accrues interest on these receivables if collectability is reasonably assured. The Company's collection estimates are based on assumptions it believes to be reasonable, but are inherently uncertain. Actual future cash flows could differ from these estimates. The decrease in Argentina financing receivables was primarily due to planned collections and unfavorable FX impacts. FONINVEMEM Agreements — As a result of energy market reforms in 2004 and 2010, AES Argentina entered into three agreements with the Argentine government, referred to as the FONINVEMEM Agreements, to contribute a portion of their accounts receivable into a fund for financing the construction of combined cycle and gas-fired plants. These receivables accrue interest and are collected in monthly installments over 10 years once the related plant begins operations. In addition, AES Argentina receives an ownership interest in these newly built plants once the receivables have been fully repaid. The FONINVEMEM receivables are denominated in Argentine pesos, but indexed to U.S. dollars, which represents a foreign currency derivative. As of December 31, 2017 and 2016 , the amount of the foreign currency-related derivative assets associated with the FONINVEMEM financing receivables that were excluded from the table above had a fair value of $240 million and $255 million , respectively. The receivables under the FONINVEMEM Agreements have been actively collected since the related plants commenced operations in 2010 and 2016. In assessing the collectability of the receivables under these agreements, the Company also considers historic collection evidence in accordance with the agreements. Other Agreements — Other agreements primarily consist of resolutions passed by the Argentine government in which AES Argentina will receive compensation for investments in new generation plants and technologies. The timing of collections depend on corresponding agreements and collectability of these receivables are assessed on an ongoing basis.

Investments In and Advances To

Investments In and Advances To Affiliates	12 Months Ended
	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
INVESTMENTS IN AND ADVANCES TO AFFILIATES	INVESTMENTS IN AND ADVANCES TO AFFILIATES The following table summarizes the relevant effective equity ownership interest and carrying values for the Company's investments accounted for under the equity method as of the periods indicated: December 31, 2017 2016 2017 2016 Affiliate Country Carrying Value (in millions) Ownership Interest % sPower United States $ 508 $ — 50 % — % Guacolda (1) Chile 357 362 33 % 33 % OPGC (2) India 269 195 49 % 49 % Elsta (3) Netherlands 38 41 50 % 50 % Equity method investments of Distributed Energy (3) United States 15 22 95 % 95 % Barry (3) United Kingdom — — 100 % 100 % Other affiliates Various 10 1 Total $ 1,197 $ 621 _____________________________ (1) The Company's ownership in Guacolda is held through AES Gener, a 67% -owned consolidated subsidiary. AES Gener owns 50% of Guacolda, resulting in an AES effective ownership in Guacolda of 33% . (2) OPGC has one coal-fired project under development which is an expansion of our existing OPGC business. The project started construction in April 2014 and is expected to begin operations in 2019. (3) Represent VIEs in which the Company holds a variable interest, but is not the primary beneficiary. sPower — In February 2017, the Company and Alberta Investment Management Corporation (“AIMCo”) entered into an agreement to acquire FTP Power LLC (“sPower”). In July 2017, AES closed on the acquisition of its 48% ownership interest in sPower for $461 million . In November 2017, AES acquired an additional 2% ownership interest in sPower for $19 million . As the Company does not control sPower, it is accounted for as an equity method investment. The sPower portfolio includes solar and wind projects in operation, under construction, and in development located in the United States. The sPower equity method investment is reported in the US SBU reportable segment. Guacolda — In September 2015, AES Gener and Global Infrastructure Partners ("GIP") executed a restructuring of Guacolda that increased Guacolda's tax basis in certain long-term assets and AES Gener's equity investment. As a result, AES Gener recorded $66 million in net equity in earnings of affiliates for the year ended December 31, 2015, of which $46 million is attributable to The AES Corporation. AES Barry Ltd. — The Company holds a 100% ownership interest in AES Barry Ltd. ("Barry"), a dormant entity in the U.K. that disposed of its generation and other operating assets. Due to a debt agreement, no material financial or operating decisions can be made without the banks' consent, and the Company does not control Barry. As of December 31, 2017 and 2016 , other long-term liabilities included $45 million and $41 million related to this debt agreement. Summarized Financial Information — The following tables summarize financial information of the Company's 50%-or-less-owned affiliates and majority-owned unconsolidated subsidiaries that are accounted for using the equity method (in millions): 50%-or-less Owned Affiliates Majority-Owned Unconsolidated Subsidiaries Years ended December 31, 2017 2016 2015 2017 2016 2015 Revenue $ 762 $ 586 $ 641 $ 16 $ 23 $ 24 Operating margin 165 145 152 5 9 11 Net income (loss) 72 64 210 (15 ) (2 ) 6 December 31, 2017 2016 2017 2016 Current assets $ 418 $ 308 $ 70 $ 16 Noncurrent assets 5,372 2,577 102 181 Current liabilities 633 626 10 10 Noncurrent liabilities 2,629 1,209 147 122 Stockholders' equity 2,527 1,048 15 65 At December 31, 2017 , retained earnings included $254 million related to the undistributed earnings of the Company's 50%-or-less owned affiliates. Distributions received from these affiliates were $69 million , $24 million , and $18 million for the years ended December 31, 2017 , 2016 , and 2015 , respectively. As of December 31, 2017 , the aggregate carrying amount of our investments in equity affiliates exceeded the underlying equity in their net assets by $46 million .

Other Non-Operating Expense Oth

Other Non-Operating Expense Other Non-Operating Expense	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
OTHER NON-OPERATING EXPENSE	OTHER NON-OPERATING EXPENSE There were no significant non-operating expenses for the years ended December 31, 2017 , 2016 or 2015 .

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS	GOODWILL AND OTHER INTANGIBLE ASSETS Goodwill — The following table summarizes the carrying amount of goodwill by reportable segment for the years ended December 31, 2017 and 2016 (in millions): US Andes MCAC Eurasia Total Balance as of December 31, 2016 Goodwill $ 2,674 $ 899 $ 149 $ 190 $ 3,912 Accumulated impairment losses (2,633 ) — — (122 ) (2,755 ) Net balance 41 899 149 68 1,157 Transfer to assets held-for-sale (1) — (30 ) — (68 ) (98 ) Balance as of December 31, 2017 Goodwill 2,674 869 149 122 3,814 Accumulated impairment losses (2,633 ) — — (122 ) (2,755 ) Net balance $ 41 $ 869 $ 149 $ — $ 1,059 _____________________________ (1) See Note 22 --- Held-For-Sale Businesses and Dispositions for further information. DP&L — During the fourth quarter of 2015, the Company performed the annual goodwill impairment test at its DP&L reporting unit and recognized a goodwill impairment expense of $317 million . The reporting unit failed Step 1 as its fair value was less than its carrying amount, which was primarily due to a decrease in forecasted dark spreads that were driven by decreases in projected forward power prices, and lower than expected revenues from a new CP product. The fair value of the reporting unit was determined under the income approach using a discounted cash flow valuation model. The significant assumptions included within the discounted cash flow valuation model were forward commodity price curves, the amount of non-bypassable charges from the pending ESP, expected revenues from the new CP product, and planned environmental expenditures. In Step 2, goodwill was determined to have an implied negative fair value after the hypothetical purchase price allocation under the accounting guidance for business combinations; therefore, a full impairment of the remaining goodwill balance of $317 million was recognized. DP&L is reported in the US SBU reportable segment. Other Intangible Assets — The following table summarizes the balances comprising Other intangible assets in the accompanying Consolidated Balance Sheets (in millions) as of the periods indicated: December 31, 2017 December 31, 2016 Gross Balance Accumulated Amortization Net Balance Gross Balance Accumulated Amortization Net Balance Subject to Amortization Internal-use software $ 416 $ (330 ) $ 86 $ 396 $ (304 ) $ 92 Contracts 92 (21 ) 71 53 (15 ) 38 Contractual payment rights (1) 65 (47 ) 18 56 (42 ) 14 Project development rights 57 (1 ) 56 4 (1 ) 3 Other (2) 98 (42 ) 56 103 (37 ) 66 Subtotal 728 (441 ) 287 612 (399 ) 213 Indefinite-Lived Intangible Assets Land use rights 45 — 45 47 — 47 Water rights 20 — 20 17 — 17 Other 14 — 14 10 — 10 Subtotal 79 — 79 74 — 74 Total $ 807 $ (441 ) $ 366 $ 686 $ (399 ) $ 287 _____________________________ (1) Represent legal rights to receive system reliability payments from the regulator. (2) Includes management rights, sales concessions, gas extraction rights, and other individually insignificant intangible assets. The following tables summarize other intangible assets acquired during the periods indicated (in millions): December 31, 2017 Amount Subject to Amortization/Indefinite-Lived Weighted Average Amortization Period (in years) Amortization Method Project Development Rights $ 53 Subject to Amortization 30 Straight-line Contracts 34 Subject to Amortization 25 Straight-line Internal-use software 17 Subject to Amortization 7 Straight-line Other 8 Various N/A N/A Total $ 112 December 31, 2016 Amount Subject to Amortization/Indefinite-Lived Weighted Average Amortization Period (in years) Amortization Method Internal-use software $ 41 Subject to Amortization 4 Straight-line Contracts 24 Subject to Amortization 26 Straight-line Other 5 Subject to Amortization 13 Straight-line Total $ 70 The following table summarizes the estimated amortization expense by intangible asset category for 2018 through 2022 : (in millions) 2018 2019 2020 2021 2022 Internal-use software $ 17 $ 14 $ 12 $ 10 $ 9 Contracts 5 5 5 5 5 Other 11 12 10 8 9 Total $ 33 $ 31 $ 27 $ 23 $ 23 Intangible asset amortization expense was $34 million , $37 million and $47 million for the years ended December 31, 2017 , 2016 and 2015 , respectively.

Regulatory Assets and Liabiliti

Regulatory Assets and Liabilities	12 Months Ended
	Dec. 31, 2017
Regulated Operations [Abstract]
REGULATORY ASSETS AND LIABILITIES	REGULATORY ASSETS AND LIABILITIES The Company has recorded regulatory assets and liabilities (in millions) that it expects to pass through to its customers in accordance with, and subject to, regulatory provisions as follows: December 31, 2017 2016 Recovery/Refund Period REGULATORY ASSETS Current regulatory assets: El Salvador tariff recoveries $ 59 $ 54 Quarterly as part of the tariff adjustment Other 60 34 Various Total current regulatory assets 119 88 Noncurrent regulatory assets: IPL and DPL defined benefit pension obligations (1) 298 316 Various IPL and DPL income taxes recoverable from customers (1) — 87 Various IPL deferred Midwest ISO costs 102 114 9 years IPL environmental costs 48 41 Various Other 94 97 Various Total noncurrent regulatory assets 542 655 TOTAL REGULATORY ASSETS $ 661 $ 743 REGULATORY LIABILITIES Current regulatory liabilities: DPL efficiency program costs $ 10 $ 14 Annually as part of the tariff adjustment Other 7 27 Various Total current regulatory liabilities 17 41 Noncurrent regulatory liabilities: IPL and DPL asset retirement obligations 830 795 Over life of assets IPL and DPL deferred income taxes 243 2 Various Other 6 5 Various Total noncurrent regulatory liabilities 1,079 802 TOTAL REGULATORY LIABILITIES $ 1,096 $ 843 _____________________________ (1) Past expenditures on which the Company earns a rate of return . Our regulatory assets primarily consist of costs that are generally non-controllable, such as purchased electricity, energy transmission, the difference between actual fuel costs and the fuel costs recovered in the tariffs, and other sector costs. These costs are recoverable or refundable as defined by the laws and regulations in our various markets. Our regulatory assets also include defined pension and postretirement benefit obligations equal to the previously unrecognized actuarial gains and losses and prior services costs that are expected to be recovered through future rates. Other current and noncurrent regulatory assets primarily consist of: • Demand charges at DPL; • Unamortized premiums reacquired or redeemed on long term debt at IPL and DPL, which are amortized over the lives of the original issuances; and • Unrecovered fuel and purchased power costs at IPL and DPL. Our regulatory liabilities primarily consist of obligations for removal costs which do not have an associated legal retirement obligation. Our regulatory liabilities also include deferred income taxes associated with the reduction of the U.S. federal income tax rate which will be passed through to our regulated customers via a decrease in future retail rates, see Note 20 — Income Taxes for further information. In the accompanying Consolidated Balance Sheets the current regulatory assets and liabilities are reflected in Other current assets and Accrued and other liabilities , respectively, and the noncurrent regulatory assets and liabilities are reflected in Other noncurrent assets and Other noncurrent liabilities , respectively. The following table summarizes regulatory assets and liabilities by reportable segment in millions as of the periods indicated: December 31, 2017 December 31, 2016 Regulatory Assets Regulatory Liabilities Regulatory Assets Regulatory Liabilities US SBU $ 602 $ 1,095 $ 689 $ 842 MCAC SBU 59 — 54 — Brazil SBU — 1 — 1 Total $ 661 $ 1,096 $ 743 $ 843

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
DEBT	DEBT NON-RECOURSE DEBT — The following table summarizes the carrying amount and terms of non-recourse debt at our subsidiaries as of the periods indicated (in millions): NON-RECOURSE DEBT Weighted Average Interest Rate Maturity December 31, 2017 2016 Variable Rate: (1) Bank loans 4.52% 2018 – 2050 $ 2,488 $ 2,601 Notes and bonds 8.06% 2020 – 2026 900 471 Debt to (or guaranteed by) multilateral, export credit agencies or development banks (2) 3.28% 2023 – 2034 3,668 3,189 Fixed Rate: Bank loans 4.54% 2018 – 2040 993 767 Notes and bonds 5.68% 2019 – 2073 7,388 7,822 Debt to (or guaranteed by) multilateral, export credit agencies or development banks (2) 5.35% 2023 – 2034 271 328 Other 5.81% 2018 – 2061 26 30 Unamortized (discount) premium & debt issuance (costs), net (394 ) (425 ) Subtotal $ 15,340 $ 14,783 Less: Current maturities (2,164 ) (1,052 ) Noncurrent maturities $ 13,176 $ 13,731 _____________________________ (1) The interest rate on variable rate debt represents the total of a variable component that is based on changes in an interest rate index and of a fixed component. The Company has interest rate swaps and option agreements in an aggregate notional principal amount of approximately $3.6 billion on non-recourse debt outstanding at December 31, 2017 . These agreements economically fix the variable component of the interest rates on the portion of the variable-rate debt being hedged so that the total interest rate on that debt has been fixed at rates ranging from approximately 2.49% to 8.00% . The debt agreements expire at various dates from 2018 through 2073 . (2) Multilateral loans include loans funded and guaranteed by bilaterals, multilaterals, development banks and other similar institutions. Non-recourse debt as of December 31, 2017 is scheduled to reach maturity as shown below (in millions): December 31, Annual Maturities 2018 $ 2,245 2019 796 2020 1,396 2021 1,833 2022 1,768 Thereafter 7,696 Unamortized (discount) premium & debt issuance (costs), net (394 ) Total $ 15,340 As of December 31, 2017 , AES subsidiaries with facilities under construction had a total of approximately $1.8 billion of committed but unused credit facilities available to fund construction and other related costs. Excluding these facilities under construction, AES subsidiaries had approximately $1.7 billion in a number of available but unused committed credit lines to support their working capital, debt service reserves and other business needs. These credit lines can be used for borrowings, letters of credit, or a combination of these uses. Significant transactions — During the year ended December 31, 2017 , the Company's subsidiaries had the following significant debt transactions: Subsidiary Issuances Repayments Gain (Loss) on Extinguishment of Debt IPALCO $ 608 $ (528 ) $ (9 ) Tietê 585 (293 ) (5 ) Southland 557 — — Gener 335 (426 ) (20 ) AES Argentina 310 (181 ) 65 Los Mina 303 (275 ) (4 ) Colon 262 — — Masinloc 160 (51 ) — DPL 103 (249 ) (3 ) Other 285 (547 ) (1 ) Total $ 3,508 $ (2,550 ) $ 23 Southland — In June 2017, AES Southland Energy LLC closed on $2 billion of aggregate principal long-term non-recourse debt financing to fund the Southland re-powering construction projects (“the Southland financing”). The Southland financing consists of $1.5 billion senior secured notes, amortizing through 2040 , and $492 million senior secured term loan, amortizing through 2027 . The long-term debt financing has a combined weighted average cost of approximately 4.5% . As of December 31, 2017 , $557 million of the senior secured notes were outstanding under the Southland financing. AES Argentina — In February 2017, AES Argentina issued $300 million aggregate principal of unsecured and unsubordinated notes due in 2024 . The net proceeds from this issuance were used for the prepayment of $75 million of non-recourse debt related to the construction of the San Nicolas Plant resulting in a gain on extinguishment of debt of approximately $65 million . Non-Recourse Debt Covenants, Restrictions and Defaults — The terms of the Company's non-recourse debt include certain financial and nonfinancial covenants. These covenants are limited to subsidiary activity and vary among the subsidiaries. These covenants may include, but are not limited to, maintenance of certain reserves and financial ratios, minimum levels of working capital and limitations on incurring additional indebtedness. As of December 31, 2017 and 2016 , approximately $642 million and $535 million , respectively, of restricted cash was maintained in accordance with certain covenants of the non-recourse debt agreements, and these amounts were included within Restricted cash and Debt service reserves and other deposits in the accompanying Consolidated Balance Sheets. Various lender and governmental provisions restrict the ability of certain of the Company's subsidiaries to transfer their net assets to the Parent Company. Such restricted net assets of subsidiaries amounted to approximately $2.8 billion at December 31, 2017 . The following table summarizes the Company's subsidiary non-recourse debt in default (in millions) as of December 31, 2017 . Due to the defaults, these amounts are included in the current portion of non-recourse debt: Primary Nature December 31, 2017 Subsidiary Default Net Assets Alto Maipo (Chile) Covenant $ 618 $ 352 AES Puerto Rico Covenant/Payment 365 692 AES Ilumina Covenant 36 54 Total $ 1,019 The amounts in default related to Puerto Rico are covenant and payment defaults. In November 2017, AES Puerto Rico signed Forbearance and Standstill Agreements with their lenders to prevent the lenders from taking action against the Company due to these default events. These agreements will expire on March 22, 2018. All other defaults listed are not payment defaults. All of the subsidiary non-recourse defaults were triggered by failure to comply with covenants and/or conditions such as (but not limited to) failure to meet information covenants, complete construction or other milestones in an allocated time, meet certain minimum or maximum financial ratios, or other requirements contained in the non-recourse debt documents of the applicable subsidiary. The AES Corporation's recourse debt agreements include cross-default clauses that will trigger if a subsidiary or group of subsidiaries for which the non-recourse debt is in default provides 20% or more of the Parent Company's total cash distributions from businesses for the four most recently completed fiscal quarters. As of December 31, 2017 , the Company has no defaults which result in or are at risk of triggering a cross-default under the recourse debt of the Parent Company. In the event the Parent Company is not in compliance with the financial covenants of its senior secured revolving credit facility, restricted payments will be limited to regular quarterly shareholder dividends at the then-prevailing rate. Payment defaults and bankruptcy defaults would preclude the making of any restricted payments. RECOURSE DEBT — The following table summarizes the carrying amount and terms of recourse debt of the Company as of the periods indicated (in millions): Interest Rate Final Maturity December 31, 2017 December 31, 2016 Senior Unsecured Note LIBOR + 3.00% 2019 $ — $ 240 Senior Unsecured Note 8.00% 2020 228 469 Senior Unsecured Note 7.38% 2021 690 966 Drawings on secured credit facility LIBOR + 2.00% 2021 207 — Senior Secured Term Loan LIBOR + 2.00% 2022 521 — Senior Unsecured Note 4.88% 2023 713 713 Senior Unsecured Note 5.50% 2024 738 738 Senior Unsecured Note 5.50% 2025 573 573 Senior Unsecured Note 6.00% 2026 500 500 Senior Unsecured Note 5.13% 2027 500 — Term Convertible Trust Securities 6.75% 2029 — 517 Unamortized (discount) premium & debt issuance (costs), net (40 ) (45 ) Subtotal $ 4,630 $ 4,671 Less: Current maturities (5 ) — Noncurrent maturities $ 4,625 $ 4,671 The following table summarizes the principal amounts due under our recourse debt for the next five years and thereafter (in millions): December 31, Net Principal Amounts Due 2018 $ 5 2019 5 2020 234 2021 902 2022 500 Thereafter 3,024 Unamortized (discount) premium & debt issuance (costs), net (40 ) Total recourse debt $ 4,630 In August 2017, the Company issued $500 million aggregate principal amount of 5.125% senior notes due in 2027 . The Company used these proceeds to redeem at par $240 million aggregate principal of its existing LIBOR + 3.00% senior unsecured notes due in 2019 and repurchased $217 million of its existing 8.00% senior unsecured notes due in 2020 . As a result of the latter transactions, the Company recognized a loss on extinguishment of debt of $36 million . In May 2017, the Company closed on $525 million aggregate principal LIBOR + 2.00% secured term loan due in 2022 . In June 2017, the Company used these proceeds to redeem at par all $517 million aggregate principal of its existing Term Convertible Securities. As a result of the latter transaction, the Company recognized a loss on extinguishment of debt of $6 million . In March 2017, the Company redeemed via tender offers $276 million aggregate principal of its existing 7.375% senior unsecured notes due in 2021 and $24 million of its existing 8.00% senior unsecured notes due in 2020 . As a result of these transactions, the Company recognized a loss on extinguishment of debt of $47 million . In July 2016, the Company redeemed in full the $181 million balance of its 8.00% outstanding senior unsecured notes due 2017 using proceeds from its senior secured credit facility. As a result, the Company recognized a loss on extinguishment of debt of $16 million . In May 2016, the Company issued $500 million aggregate principal amount of 6.00% senior notes due 2026 . The Company used these proceeds to redeem, at par, $495 million aggregate principal of its existing LIBOR + 3.00% senior unsecured notes due 2019 . As a result of the latter transaction, the Company recognized a loss on extinguishment of debt of $4 million . In January 2016, the Company redeemed $125 million of its senior unsecured notes outstanding. The repayment included a portion of the 7.375% senior notes due in 2021 , the 4.875% senior notes due in 2023 , the 5.5% senior notes due in 2024 , the 5.5% senior notes due in 2025 and the floating rate senior notes due in 2019 . As a result of these transactions, the Company recognized a net gain on extinguishment of debt of $7 million . Recourse Debt Covenants and Guarantees — The Company's obligations under the senior secured credit facility and senior secured term loan are, subject to certain exceptions, secured by (i) all of the capital stock of domestic subsidiaries owned directly by the Company and 65% of the capital stock of certain foreign subsidiaries owned directly or indirectly by the Company; and (ii) certain intercompany receivables, certain intercompany notes and certain intercompany tax sharing agreements. The senior secured credit facility and senior secured term loan is subject to mandatory prepayment under certain circumstances, including the sale of certain assets. In such a situation, the net cash proceeds from the sale must be applied pro rata to repay the term loan, if any, using 60% of net cash proceeds, reduced to 50% when and if the parent's recourse debt to cash flow ratio is less than 5:1 . The lenders have the option to waive their pro rata redemption. The senior secured credit facility contains customary covenants and restrictions on the Company's ability to engage in certain activities, including, but not limited to, limitations on other indebtedness, liens, investments and guarantees; limitations on restricted payments such as shareholder dividends and equity repurchases; restrictions on mergers and acquisitions, sales of assets, leases, transactions with affiliates and off-balance sheet or derivative arrangements; and other financial reporting requirements. The senior secured credit facility also contains financial covenants, evaluated quarterly, requiring the Company to maintain a minimum ratio of adjusted operating cash flow to interest charges on recourse debt of 1.3 times and a maximum ratio of recourse debt to adjusted operating cash flow of 7.5 times. The terms of the Company's senior unsecured notes and senior secured term loan contain certain covenants including, without limitation, limitation on the Company's ability to incur liens or enter into sale and leaseback transactions. TERM CONVERTIBLE TRUST SECURITIES — In 1999, AES Trust III, a wholly-owned special purpose business trust and a VIE, issued approximately 10.35 million of $50 par value TECONS with a quarterly coupon payment of $0.844 for total proceeds of $517 million and concurrently purchased $517 million of 6.75% Junior Subordinated Convertible Debentures due 2029 (the "6.75% Debentures") issued by AES. AES, at its option, may redeem the 6.75% Debentures which would result in the required redemption of the TECONS issued by AES Trust III for $50 per TECON. As of December 31, 2016 , the sole assets of AES Trust III were the 6.75% Debentures. In June 2017, the Company redeemed the 6.75% Debentures and redeemed at par all remaining aggregate principal of its existing TECONs.

Commitments

Commitments	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS	COMMITMENTS LEASES — The Company enters into long-term non-cancelable lease arrangements which, for accounting purposes, are classified as either operating or capital leases. Operating leases primarily include certain transmission lines, office rental and site leases. Operating lease rental expense for the years ended December 31, 2017 , 2016 , and 2015 was $61 million , $61 million and $45 million , respectively. Capital leases primarily include transmission lines, vehicles, offices, and other operating equipment. Capital leases are recognized in Property, Plant and Equipment within Electric generation, distribution assets and other . The gross value of the capital lease assets as of December 31, 2017 and 2016 was $27 million and $22 million , respectively. The following table shows the future minimum lease payments under operating and capital leases for continuing operations together with the present value of the net minimum lease payments under capital leases as of December 31, 2017 for 2018 through 2022 and thereafter (in millions): Future Commitments for December 31, Capital Leases Operating Leases 2018 $ 2 $ 58 2019 1 58 2020 1 58 2021 1 59 2022 1 58 Thereafter 12 644 Total $ 18 $ 935 Less: Imputed interest (10 ) Present value of total minimum lease payments $ 8 CONTRACTS — The Company enters into long-term contracts for construction projects, maintenance and service, transmission of electricity, operations services and purchase of electricity and fuel. In general, these contracts are subject to variable quantities or prices and are terminable only in limited circumstances. The following table shows the future minimum commitments for continuing operations under these contracts as of December 31, 2017 for 2018 through 2022 and thereafter as well as actual purchases under these contracts for the years ended December 31, 2017 , 2016 , and 2015 (in millions): Actual purchases during the year ended December 31, Electricity Purchase Contracts Fuel Purchase Contracts Other Purchase Contracts 2015 $ 545 $ 1,262 $ 1,833 2016 420 1,790 817 2017 747 1,619 1,945 Future commitments for the year ending December 31, 2018 $ 581 $ 1,759 $ 1,488 2019 508 1,051 931 2020 440 591 470 2021 469 538 234 2022 438 454 547 Thereafter 2,065 1,466 1,314 Total $ 4,501 $ 5,859 $ 4,984

Contingencies

Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
CONTINGENCIES	CONTINGENCIES Guarantees and Letters of Credit — In connection with certain project financings, acquisitions and dispositions, power purchases and other agreements, the Parent Company has expressly undertaken limited obligations and commitments, most of which will only be effective or will be terminated upon the occurrence of future events. In the normal course of business, the Parent Company has entered into various agreements, mainly guarantees and letters of credit, to provide financial or performance assurance to third parties on behalf of AES businesses. These agreements are entered into primarily to support or enhance the creditworthiness otherwise achieved by a business on a stand-alone basis, thereby facilitating the availability of sufficient credit to accomplish their intended business purposes. Most of the contingent obligations relate to future performance commitments which the Company expects to fulfill within the normal course of business. The expiration dates of these guarantees vary from less than one year to more than 17 years . The following table summarizes the Parent Company's contingent contractual obligations as of December 31, 2017 . Amounts presented in the following table represent the Parent Company's current undiscounted exposure to guarantees and the range of maximum undiscounted potential exposure. The maximum exposure is not reduced by the amounts, if any, that could be recovered under the recourse or collateralization provisions in the guarantees. There were no obligations made by the Parent Company for the direct benefit of the lenders associated with the non-recourse debt of its businesses. Contingent Contractual Obligations Amount (in millions) Number of Agreements Maximum Exposure Range for Each Agreement (in millions) Guarantees and commitments $ 815 21 $1 — 272 Letters of credit under the unsecured credit facility 52 4 $2 — 26 Asset sale related indemnities (1) 27 1 27 Letters of credit under the senior secured credit facility 36 21 <$1 — 13 Total $ 930 47 _____________________________ (1) Excludes normal and customary representations and warranties in agreements for the sale of assets (including ownership in associated legal entities) where the associated risk is considered to be nominal. During the year ended December 31, 2017 , the Company paid letter of credit fees ranging from 0.25% to 2.25% per annum on the outstanding amounts of letters of credit. Environmental — The Company periodically reviews its obligations as they relate to compliance with environmental laws, including site restoration and remediation. As of December 31, 2017 and 2016 the Company had recognized liabilities of $5 million and $9 million , respectively, for projected environmental remediation costs. Due to the uncertainties associated with environmental assessment and remediation activities, future costs of compliance or remediation could be higher or lower than the amount currently accrued. Moreover, where no liability has been recognized, it is reasonably possible that the Company may be required to incur remediation costs or make expenditures in amounts that could be material but could not be estimated as of December 31, 2017 . In aggregate, the Company estimates that the range of potential losses related to environmental matters, where estimable, to be up to $18 million . The amounts considered reasonably possible do not include amounts accrued as discussed above. Litigation — The Company is involved in certain claims, suits and legal proceedings in the normal course of business. The Company accrues for litigation and claims when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. The Company has recognized aggregate liabilities for all claims of approximately $50 million and $59 million as of December 31, 2017 and 2016 , respectively. These amounts are reported on the Consolidated Balance Sheets within Accrued and other liabilities and Other noncurrent liabilities . A significant portion of these accrued liabilities relate to regulatory matters and commercial disputes in international jurisdictions. There can be no assurance that these accrued liabilities will be adequate to cover all existing and future claims or that we will have the liquidity to pay such claims as they arise. Where no accrued liability has been recognized, it is reasonably possible that some matters could be decided unfavorably to the Company and could require the Company to pay damages or make expenditures in amounts that could be material but could not be estimated as of December 31, 2017 . The material contingencies where a loss is reasonably possible primarily include claims under financing agreements; disputes with offtakers, suppliers and EPC contractors; alleged violation of monopoly laws and regulations; income tax and non-income tax matters with tax authorities; and regulatory matters. In aggregate, the Company estimates that the range of potential losses, where estimable, related to these reasonably possible material contingencies to be between $140 million and $173 million . The amounts considered reasonably possible do not include amounts accrued, as discussed above. These material contingencies do not include income tax-related contingencies which are considered part of our uncertain tax positions.

Benefit Plans

Benefit Plans	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
BENEFIT PLANS	BENEFIT PLANS Defined Contribution Plan — The Company sponsors four defined contribution plans ("the DC Plans"). Two plans cover U.S. non-union employees; one for Parent Company and certain US SBU business employees, and one for DPL employees. The remaining two plans include union and non-union employees at IPL and union employees at DPL. The DC Plans are qualified under section 401 of the Internal Revenue Code. Most U.S. employees of the Company are eligible to participate in the appropriate plan except for those employees who are covered by a collective bargaining agreement, unless such agreement specifically provides that the employee is considered an eligible employee under a plan. Within the DC Plans, the Company provides matching contributions in addition to other non-matching contributions. Participants are fully vested in their own contributions. The Company's contributions vest over various time periods ranging from immediate up to five years. For the years ended December 31, 2017 , 2016 and 2015 , costs for defined contribution plans were approximately $23 million , $15 million and $18 million , respectively. Defined Benefit Plans — Certain of the Company's subsidiaries have defined benefit pension plans covering substantially all of their respective employees ("the DB Plans"). Pension benefits are based on years of credited service, age of the participant, and average earnings. Of the 31 active DB Plans as of December 31, 2017 , five are at U.S. subsidiaries and the remaining plans are at foreign subsidiaries . The following table reconciles the Company's funded status, both domestic and foreign, as of the periods indicated (in millions): 2017 2016 U.S. Foreign U.S. Foreign CHANGE IN PROJECTED BENEFIT OBLIGATION: Benefit obligation as of January 1 $ 1,188 $ 411 $ 1,172 $ 374 Service cost 13 10 13 9 Interest cost 41 22 42 21 Employee contributions — 1 — 1 Plan amendments 1 (1 ) — (4 ) Plan curtailments 3 — 2 — Plan settlements — (2 ) — — Benefits paid (71 ) (22 ) (60 ) (19 ) Actuarial loss 82 29 19 58 Effect of foreign currency exchange rate changes — 22 — (29 ) Benefit obligation as of December 31 $ 1,257 $ 470 $ 1,188 $ 411 CHANGE IN PLAN ASSETS: Fair value of plan assets as of January 1 $ 1,044 $ 402 $ 1,021 $ 379 Actual return on plan assets 141 31 61 59 Employer contributions 13 18 22 18 Employee contributions — 1 — 1 Plan settlements — (2 ) — — Benefits paid (71 ) (22 ) (60 ) (19 ) Effect of foreign currency exchange rate changes — 27 — (36 ) Fair value of plan assets as of December 31 $ 1,127 $ 455 $ 1,044 $ 402 RECONCILIATION OF FUNDED STATUS Funded status as of December 31 $ (130 ) $ (15 ) $ (144 ) $ (9 ) The following table summarizes the amounts recognized on the Consolidated Balance Sheets related to the funded status of the DB Plans, both domestic and foreign, as of the periods indicated (in millions): December 31, 2017 2016 Amounts Recognized on the Consolidated Balance Sheets U.S. Foreign U.S. Foreign Noncurrent assets $ — $ 69 $ — $ 60 Accrued benefit liability—current — (6 ) — (5 ) Accrued benefit liability—noncurrent (130 ) (78 ) (144 ) (64 ) Net amount recognized at end of year $ (130 ) $ (15 ) $ (144 ) $ (9 ) The following table summarizes the Company's U.S. and foreign accumulated benefit obligation as of the periods indicated (in millions): December 31, 2017 2016 U.S. Foreign U.S. Foreign Accumulated Benefit Obligation $ 1,236 $ 433 $ 1,167 $ 384 Information for pension plans with an accumulated benefit obligation in excess of plan assets: Projected benefit obligation $ 1,257 $ 109 $ 1,188 $ 90 Accumulated benefit obligation 1,236 97 1,167 80 Fair value of plan assets 1,127 33 1,044 25 Information for pension plans with a projected benefit obligation in excess of plan assets: Projected benefit obligation $ 1,257 $ 238 $ 1,188 $ 212 Fair value of plan assets 1,127 154 1,044 142 The following table summarizes the significant weighted average assumptions used in the calculation of benefit obligation and net periodic benefit cost, both domestic and foreign, as of the periods indicated: December 31, 2017 2016 U.S. Foreign U.S. Foreign Benefit Obligation: Discount rate 3.67 % 5.23 % 4.28 % 5.83 % Rate of compensation increase 3.34 % 4.65 % 3.34 % 4.86 % Periodic Benefit Cost: Discount rate 4.28 % 5.83 % (1) 4.44 % 6.10 % (1) Expected long-term rate of return on plan assets 6.67 % 5.30 % 6.67 % 5.09 % Rate of compensation increase 3.34 % 4.86 % 3.34 % 4.45 % _____________________________ (1) Includes an inflation factor that is used to calculate future periodic benefit cost, but is not used to calculate the benefit obligation. The Company establishes its estimated long-term return on plan assets considering various factors, which include the targeted asset allocation percentages, historic returns, and expected future returns. The measurement of pension obligations, costs, and liabilities is dependent on a variety of assumptions. These assumptions include estimates of the present value of projected future pension payments to all plan participants, taking into consideration the likelihood of potential future events such as salary increases and demographic experience. These assumptions may have an effect on the amount and timing of future contributions. The assumptions used in developing the required estimates include the following key factors: discount rates; salary growth; retirement rates; inflation; expected return on plan assets; and mortality rates. The effects of actual results differing from the Company's assumptions are accumulated and amortized over future periods and, therefore, generally affect the Company's recognized expense in such future periods. Unrecognized gains or losses are amortized using the “corridor approach,” under which the net gain or loss in excess of 10% of the greater of the projected benefit obligation or the market-related value of the assets, if applicable, is amortized. Sensitivity of the Company's pension funded status to the indicated increase or decrease in the discount rate and long-term rate of return on plan assets assumptions is shown below. Note that these sensitivities may be asymmetric and are specific to the base conditions at year-end 2017 . They also may not be additive, so the impact of changing multiple factors simultaneously cannot be calculated by combining the individual sensitivities shown. The funded status as of December 31, 2017 is affected by the assumptions as of that date. Pension expense for 2017 is affected by the December 31, 2016 assumptions. The impact on pension expense from a one percentage point change in these assumptions is shown in the following table (in millions): Increase of 1% in the discount rate $ (13 ) Decrease of 1% in the discount rate 12 Increase of 1% in the long-term rate of return on plan assets (15 ) Decrease of 1% in the long-term rate of return on plan assets 15 The following table summarizes the components of the net periodic benefit cost, both domestic and foreign, for the years indicated (in millions): December 31, 2017 2016 2015 Components of Net Periodic Benefit Cost: U.S. Foreign U.S. Foreign U.S. Foreign Service cost $ 13 $ 10 $ 13 $ 9 $ 16 $ 10 Interest cost 41 23 42 21 48 23 Expected return on plan assets (69 ) (21 ) (68 ) (19 ) (70 ) (20 ) Amortization of prior service cost 6 — 7 (1 ) 7 — Amortization of net loss 18 2 18 2 20 2 Curtailment loss recognized 4 — 4 — — — Total pension cost $ 13 $ 14 $ 16 $ 12 $ 21 $ 15 The following table summarizes in millions the amounts reflected in AOCL, including AOCL attributable to noncontrolling interests, on the Consolidated Balance Sheet as of December 31, 2017 , that have not yet been recognized as components of net periodic benefit cost and amounts expected to be reclassified to earnings in the next fiscal year (in millions): December 31, 2017 Accumulated Other Comprehensive Income (Loss) Amounts expected to be reclassified to earnings in next fiscal year U.S. Foreign U.S. Foreign Prior service cost $ (1 ) $ 1 $ — $ — Unrecognized net actuarial loss (22 ) (81 ) (2 ) (3 ) Total $ (23 ) $ (80 ) $ (2 ) $ (3 ) The following table summarizes the Company's target allocation for 2017 and pension plan asset allocation, both domestic and foreign, as of the periods indicated: Percentage of Plan Assets as of December 31, Target Allocations 2017 2016 Asset Category U.S. Foreign U.S. Foreign U.S. Foreign Equity securities 33% 4% 31.90 % 4.61 % 50.96 % 18.66 % Debt securities 65% 93% 64.53 % 93.10 % 45.88 % 78.35 % Real estate 2% —% 3.20 % 0.44 % 3.16 % 0.75 % Other —% 3% 0.37 % 1.85 % — % 2.24 % Total pension assets 100.00 % 100.00 % 100.00 % 100.00 % The U.S. DB Plans seek to achieve the following long-term investment objectives: • maintenance of sufficient income and liquidity to pay retirement benefits and other lump sum payments; • long-term rate of return in excess of the annualized inflation rate; • long-term rate of return, net of relevant fees, that meets or exceeds the assumed actuarial rate; and • long-term competitive rate of return on investments, net of expenses, that equals or exceeds various benchmark rates. The asset allocation is reviewed periodically to determine a suitable asset allocation which seeks to manage risk through portfolio diversification and takes into account the above-stated objectives, in conjunction with current funding levels, cash flow conditions and economic and industry trends. The following table summarizes the Company's U.S. DB Plan assets by category of investment and level within the fair value hierarchy as of the periods indicated (in millions): December 31, 2017 December 31, 2016 U.S. Plans Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Equity securities: Mutual funds $ 359 $ — $ — $ 359 $ 532 $ — $ — $ 532 Debt securities: Government debt securities 135 — — 135 86 — — 86 Mutual funds (1) 593 — — 593 393 — — 393 Real estate: Real estate — 36 — 36 — 33 — 33 Other: Cash and cash equivalents 4 — — 4 — — — — Total plan assets $ 1,091 $ 36 $ — $ 1,127 $ 1,011 $ 33 $ — $ 1,044 _____________________________ (1) Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment. The investment strategy of the foreign DB Plans seeks to maximize return on investment while minimizing risk. The assumed asset allocation has less exposure to equities in order to closely match market conditions and near term forecasts. The following table summarizes the Company's foreign DB plan assets by category of investment and level within the fair value hierarchy as of the periods indicated (in millions): December 31, 2017 December 31, 2016 Foreign Plans Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Equity securities: Mutual funds $ 20 $ — $ — $ 20 $ 71 $ — $ — $ 71 Private equity — — 1 1 — — 4 4 Debt securities: Government debt securities 11 — — 11 10 — — 10 Mutual funds (1) 323 90 — 413 215 90 — 305 Real estate: Real estate — — 2 2 — — 3 3 Other: Participant loans (2) — — — — — — 2 2 Other assets 1 — 7 8 4 — 3 7 Total plan assets $ 355 $ 90 $ 10 $ 455 $ 300 $ 90 $ 12 $ 402 _____________________________ (1) Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment. (2) Loans to participants are stated at cost, which approximates fair value. The following table summarizes the estimated cash flows for U.S. and foreign expected employer contributions and expected future benefit payments, both domestic and foreign (in millions): U.S. Foreign Expected employer contribution in 2018 $ 39 $ 15 Expected benefit payments for fiscal year ending: 2018 71 23 2019 73 23 2020 74 25 2021 75 26 2022 76 27 2023 - 2027 380 170

Equity

Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Equity	EQUITY Equity Transactions with Noncontrolling Interests Alto Maipo — In March 2017, AES Gener completed the legal and financial restructuring of Alto Maipo. As part of this restructuring, AES indirectly acquired the 40% ownership interest of the noncontrolling shareholder, for a de minimis payment, and sold a 6.7% interest in the project to the construction contractor. This transaction resulted in a $196 million increase to the Parent Company’s Stockholders’ Equity due to an increase in additional paid-in-capital of $229 million , offset by the reclassification of accumulated other comprehensive losses from NCI to the Parent Company Stockholders’ Equity of $33 million . No gain or loss was recognized in net income as the sale was not considered to be a sale of in-substance real estate. After completion of the sale, the Company has an effective 62% economic interest in Alto Maipo. As the Company maintained control of the partnership after the sale, Alto Maipo continues to be consolidated by the Company within the Andes SBU reportable segment. Dominican Republic — As part of a purchase agreement executed in 2014, Estrella and Linda Groups, an investor-based group in the Dominican Republic, had options to acquire additional interests in our businesses in the Dominican Republic. In December 2015, Estrella and Linda Groups exercised their first call option to acquire an additional 2% of our businesses in the Dominican Republic for $18 million , resulting in a net increase of $7 million to additional paid-in-capital. No gain or loss was recognized in net income as the sale was not considered to be a sale of in-substance real estate. After exercising this option, Estrella and Linda Groups held a 10% interest in our businesses in the Dominican Republic. Estrella and Linda Groups had a final option to acquire an additional 10% of our businesses in the Dominican Republic for $125 million which expired in December 2017. In September 2017, Linda Group acquired 5% of our Dominican Republic business for $60 million , pre-tax. This transaction resulted in a net increase of $25 million to the Company’s additional paid-in-capital and noncontrolling interest, respectively. No gain or loss was recognized in net income as the sale was not considered a sale of in-substance real estate. As the Company maintained control after the sale, our businesses in the Dominican Republic continue to be consolidated by the Company within the MCAC SBU reportable segment. Jordan — In February 2016, the Company completed the sale of 40% of its interest in a wholly-owned subsidiary in Jordan that owns a controlling interest in the Jordan IPP4 gas-fired plant for $21 million . The transaction was accounted for as a sale of in-substance real estate and a pre-tax gain of $4 million , net of transaction costs, was recognized in net income. The cash proceeds from the sale are reflected in Proceeds from the sale of businesses, net of cash sold on the Consolidated Statement of Cash Flows for the period ended December 31, 2016. After completion of the sale, the Company has a 36% economic interest in Jordan IPP4 and continues to manage and operate the plant, with 40% owned by Mitsui Ltd. and 24% owned by Nebras Power Q.S.C. As the Company maintained control after the sale, Jordan IPP4 continues to be consolidated by the Company within the Eurasia SBU reportable segment. Brazil Reorganization — In 2015, the Company completed a restructuring of Tietê. This transaction resulted in no change of ownership or control. The $27 million impact of this equity transaction was recognized in additional paid-in-capital. Gener — In November 2015, the Company sold a 4% stake in AES Gener S.A. ("Gener") through its 99.9% owned subsidiary Inversiones Cachagua S.p.A ("Cachagua") for $145 million , net of transaction costs. The sale was of previously issued common shares of Gener to certain institutional investors and is not a sale of in-substance real estate. While the sale decreased Parent ownership interest from 70.7% to 66.7% , the Parent continues to retain its controlling financial interest in the subsidiary. The difference of $24 million between the fair value of the consideration received, net of taxes and transaction costs, and the amount by which the NCI is adjusted was recognized in additional paid-in-capital. No pre-tax gain or loss was recognized in net income as a result of this transaction. The following table summarizes the net income attributable to The AES Corporation and all transfers (to) from noncontrolling interests for the periods indicated (in millions): December 31, 2017 2016 2015 Net income (loss) attributable to The AES Corporation $ (1,161 ) $ (1,130 ) $ 306 Transfers from noncontrolling interest: Net increase in The AES Corporation's paid-in capital for sale of subsidiary shares 13 84 323 Additional paid-in-capital, IPALCO shares, transferred to redeemable stock of subsidiaries (1) — (84 ) (377 ) Increase (decrease) in The AES Corporation's paid-in-capital for purchase of subsidiary shares 240 (2 ) — Net transfers (to) from noncontrolling interest 253 (2 ) (54 ) Change from net income (loss) attributable to The AES Corporation and transfers (to) from noncontrolling interests $ (908 ) $ (1,132 ) $ 252 _____________________________ (1) See Note 17 — Redeemable stock of subsidiaries for further information on increase in paid-in-capital transferred to redeemable stock of subsidiaries. Deconsolidations UK Wind — During 2016, the Company determined it no longer had control of its wind development projects in the United Kingdom (“UK Wind”) as the Company no longer held seats on the board of directors. In accordance with accounting guidance, UK Wind was deconsolidated and a loss on deconsolidation of $20 million was recorded to Gain (loss) on disposal and sale of businesses in the Consolidated Statement of Operations to write off the Company’s noncontrolling interest in the project. The UK Wind projects were reported in the Eurasia SBU reportable segment. Accumulated Other Comprehensive Loss — The changes in AOCL by component, net of tax and noncontrolling interests, for the periods indicated were as follows (in millions): Foreign currency translation adjustment, net Unrealized derivative losses, net Unfunded pension obligations, net Total Balance at December 31,2015 $ (3,256 ) $ (353 ) $ (274 ) $ (3,883 ) Other comprehensive income (loss) before reclassifications 117 2 (13 ) 106 Amount reclassified to earnings 992 28 1 1,021 Other comprehensive income (loss) $ 1,109 $ 30 $ (12 ) $ 1,127 Balance at December 31, 2016 $ (2,147 ) $ (323 ) $ (286 ) $ (2,756 ) Other comprehensive loss before reclassifications $ 18 $ (14 ) $ (19 ) $ (15 ) Amount reclassified to earnings 643 37 248 928 Other comprehensive income $ 661 $ 23 $ 229 $ 913 Reclassification from NCI due to Alto Maipo Restructuring — (33 ) — (33 ) Balance at December 31, 2017 $ (1,486 ) $ (333 ) $ (57 ) $ (1,876 ) Reclassifications out of AOCL are presented in the following table. Amounts for the periods indicated are in millions and those in parenthesis indicate debits to the Condensed Consolidated Statements of Operations: Details About December 31, AOCL Components Affected Line Item in the Consolidated Statements of Operations 2017 2016 2015 Foreign currency translation adjustments, net Gain (loss) on disposal and sale of businesses $ (188 ) $ — $ — Net loss from disposal and impairments of discontinued operations (455 ) (992 ) — Net income (loss) attributable to The AES Corporation $ (643 ) $ (992 ) $ — Unrealized derivative gains (losses), net Non-regulated revenue $ 25 $ 111 $ 43 Non-regulated cost of sales (12 ) (57 ) (14 ) Interest expense (79 ) (107 ) (112 ) Gain (loss) on disposal and sale of businesses — — (4 ) Foreign currency transaction gains 15 8 12 Income from continuing operations before taxes and equity in earnings of affiliates (51 ) (45 ) (75 ) Income tax expense 1 8 11 Net equity in earnings of affiliates — — (2 ) Income (loss) from continuing operations (50 ) (37 ) (66 ) Less: (Income) from continuing operations attributable to noncontrolling interests 13 9 18 Net income (loss) attributable to The AES Corporation $ (37 ) $ (28 ) $ (48 ) Amortization of defined benefit pension actuarial losses, net Non-regulated cost of sales 1 — 2 General and administrative expenses (1 ) (1 ) (2 ) Other expense — (1 ) — Income from continuing operations before taxes and equity in earnings of affiliates — (2 ) — Income tax expense — 3 9 Income from continuing operations — 1 9 Net loss from disposal and impairments of discontinued operations (266 ) (11 ) (25 ) Net income (loss) (266 ) (10 ) (16 ) Less: (Income) from continuing operations attributable to noncontrolling interests — 9 14 Add: Loss from discontinued operations attributable to noncontrolling interests 18 — — Net income (loss) attributable to The AES Corporation $ (248 ) $ (1 ) $ (2 ) Total reclassifications for the period, net of income tax and noncontrolling interests $ (928 ) $ (1,021 ) $ (50 ) Common Stock Dividends — The Parent Company paid dividends of $0.12 per outstanding share to its common stockholders during the first, second, third and fourth quarters of 2017 for dividends declared in December 2016, February, July, and October 2017, respectively. On December 8, 2017, the Board of Directors declared a quarterly common stock dividend of $0.13 per share payable on February 15, 2018 to shareholders of record at the close of business on February 1, 2018. Stock Repurchase Program — No shares were repurchased in 2017. The cumulative repurchases from the commencement of the Program in July 2010 through December 31, 2017 totaled 154.3 million shares for a total cost of $1.9 billion , at an average price per share of $12.12 (including a nominal amount of commissions). As of December 31, 2017 , $246 million remained available for repurchase under the Program. The common stock repurchased has been classified as treasury stock and accounted for using the cost method. A total of 155,924,785 and 156,878,891 shares were held as treasury stock at December 31, 2017 and 2016 , respectively. Restricted stock units under the Company's employee benefit plans are issued from treasury stock. The Company has not retired any common stock repurchased since it began the Program in July 2010.

Segment and Geographic Informat

Segment and Geographic Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
SEGMENT AND GEOGRAPHIC INFORMATION	SEGMENTS AND GEOGRAPHIC INFORMATION The segment reporting structure uses the Company's organizational structure as its foundation to reflect how the Company manages the businesses internally and is organized by geographic regions which provides a socio-political-economic understanding of our business. During the third quarter of 2017, the Europe and Asia SBUs were merged in order to leverage scale and are now reported as part of the Eurasia SBU. The management reporting structure is organized by five SBUs led by our President and Chief Executive Officer: US, Andes, Brazil, MCAC and Eurasia SBUs. The Company determined that it has five operating and five reportable segments corresponding to its SBUs. All prior period results have been retrospectively revised to reflect the new segment reporting structure. In February 2018, we announced a reorganization as a part of our ongoing strategy to simplify our portfolio, optimize our cost structure, and reduce our carbon intensity. The Company is currently evaluating the impact this reorganization will have on our segment reporting structure. Corporate and Other — Corporate overhead costs which are not directly associated with the operations of our five reportable segments are included in "Corporate and Other." Also included are certain intercompany charges such as self-insurance premiums which are fully eliminated in consolidation. The Company uses Adjusted PTC as its primary segment performance measure. Adjusted PTC, a non-GAAP measure, is defined by the Company as pre-tax income from continuing operations attributable to The AES Corporation excluding gains or losses of the consolidated entity due to (a) unrealized gains or losses related to derivative transactions; (b) unrealized foreign currency gains or losses; (c) gains, losses and associated benefits and costs due to dispositions and acquisitions of business interests, including early plant closures; (d) losses due to impairments; (e) gains, losses and costs due to the early retirement of debt; and (f) costs directly associated with a major restructuring program, including, but not limited to, workforce reduction efforts, relocations, and office consolidation . Adjusted PTC also includes net equity in earnings of affiliates on an after-tax basis adjusted for the same gains or losses excluded from consolidated entities. The Company has concluded Adjusted PTC better reflects the underlying business performance of the Company and is the most relevant measure considered in the Company's internal evaluation of the financial performance of its segments. Additionally, given its large number of businesses and complexity, the Company concluded that Adjusted PTC is a more transparent measure that better assists investors in determining which businesses have the greatest impact on the Company's results. Revenue and Adjusted PTC are presented before inter-segment eliminations, which includes the effect of intercompany transactions with other segments except for interest, charges for certain management fees, and the write-off of intercompany balances, as applicable. All intra-segment activity has been eliminated within the segment. Inter-segment activity has been eliminated within the total consolidated results. The following tables present financial information by segment for the periods indicated (in millions): Total Revenue Year Ended December 31, 2017 2016 2015 US SBU $ 3,229 $ 3,429 $ 3,593 Andes SBU 2,710 2,506 2,489 Brazil SBU 542 450 962 MCAC SBU 2,448 2,172 2,353 Eurasia SBU 1,590 1,670 1,875 Corporate and Other 35 77 31 Eliminations (24 ) (23 ) (43 ) Total Revenue $ 10,530 $ 10,281 $ 11,260 Reconciliation from Income from Continuing Operations before Taxes and Equity in Earnings of Affiliates: Total Adjusted PTC Year Ended December 31, 2017 2016 2015 Income from continuing operations before taxes and equity in earnings of affiliates $ 771 $ 187 $ 989 Add: Net equity earnings in affiliates 71 36 105 Less: Income from continuing operations before taxes, attributable to noncontrolling interests (521 ) (354 ) (513 ) Pre-tax contribution 321 (131 ) 581 Unrealized derivative gains (3 ) (9 ) (166 ) Unrealized foreign currency (gains) losses (59 ) 22 95 Disposition/acquisition (gains) losses 123 6 (42 ) Impairment losses 542 933 504 Loss on extinguishment of debt 62 29 179 Restructuring costs (1) 31 — — Total Adjusted PTC $ 1,017 $ 850 $ 1,151 _____________________________ (1) One-time restructuring charges consisting of severance costs related to workforce reductions. Total Adjusted PTC Year Ended December 31, 2017 2016 2015 US SBU $ 361 $ 347 $ 360 Andes SBU 386 390 482 Brazil SBU 60 38 92 MCAC SBU 340 267 327 Eurasia SBU 290 283 331 Corporate and Other (420 ) (475 ) (441 ) Total Adjusted PTC $ 1,017 $ 850 $ 1,151 Total Assets Depreciation and Amortization Capital Expenditures Year Ended December 31, 2017 2016 2015 2017 2016 2015 2017 2016 2015 US SBU $ 9,852 $ 9,333 $ 9,800 $ 437 $ 471 $ 443 $ 858 $ 809 $ 861 Andes SBU 8,840 8,971 8,594 250 218 175 443 538 949 Brazil SBU 2,034 1,516 1,179 51 33 39 34 31 47 MCAC SBU 5,532 5,162 4,820 172 165 155 482 480 201 Eurasia SBU 4,557 5,777 6,200 127 149 166 211 279 131 Assets of discontinued operations and held-for-sale businesses 2,034 4,936 5,411 123 128 146 315 303 252 Corporate and Other 263 429 541 9 12 20 13 18 17 Total $ 33,112 $ 36,124 $ 36,545 $ 1,169 $ 1,176 $ 1,144 $ 2,356 $ 2,458 $ 2,458 Interest Income Interest Expense Year Ended December 31, 2017 2016 2015 2017 2016 2015 US SBU $ — $ — $ — $ 258 $ 236 $ 262 Andes SBU 50 57 77 205 178 154 Brazil SBU 45 38 31 92 69 58 MCAC SBU 18 11 30 168 163 179 Eurasia SBU 130 139 116 167 179 158 Corporate and Other 1 — 2 280 309 334 Total $ 244 $ 245 $ 256 $ 1,170 $ 1,134 $ 1,145 Investments in and Advances to Affiliates Net Equity in Earnings of Affiliates Year Ended December 31, 2017 2016 2015 2017 2016 2015 US SBU $ 527 $ 23 $ 1 $ 41 $ 9 $ — Andes SBU 358 363 345 28 15 83 MCAC SBU 3 (1 ) — (4 ) (2 ) — Eurasia SBU 307 236 248 9 13 18 Corporate and Other 2 — 16 (3 ) 1 4 Total $ 1,197 $ 621 $ 610 $ 71 $ 36 $ 105 The following table presents information, by country, about the Company's consolidated operations for each of the three years ended December 31, 2017 , 2016 , and 2015 , and as of December 31, 2017 and 2016 (in millions). Revenue is recorded in the country in which it is earned and assets are recorded in the country in which they are located. Total Revenue Property, Plant & Equipment, net Year Ended December 31, 2017 2016 2015 2017 2016 United States $ 3,240 $ 3,489 $ 3,597 $ 7,403 $ 7,397 Non-U.S.: Chile 1,944 1,707 1,523 5,066 4,995 Dominican Republic 826 614 632 935 914 El Salvador 686 601 736 340 327 Brazil 541 450 962 1,286 789 Philippines 449 401 406 — 866 Argentina 435 359 399 223 195 Bulgaria 367 334 382 1,290 1,174 Mexico 352 342 383 687 699 Panama 338 312 297 1,615 1,233 Colombia 332 437 557 332 451 United Kingdom 328 337 396 108 151 Vietnam (1) 278 340 233 2 1 Puerto Rico 247 301 302 565 583 Jordan 95 136 248 431 452 Kazakhstan 67 103 155 — 178 Other Non-U.S. 5 18 52 13 10 Total Non-U.S. 7,290 6,792 7,663 12,893 13,018 Total $ 10,530 $ 10,281 $ 11,260 $ 20,296 $ 20,415 _____________________________ (1) The Mong Duong II power project is accounted for as a service concession arrangement. Costs of construction of the plant have been deferred in Service concession assets on the Consolidated Balance Sheets.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
SHARE-BASED COMPENSATION	SHARE-BASED COMPENSATION RESTRICTED STOCK Restricted Stock Units — The Company issues restricted stock units ("RSUs") under its long-term compensation plan. The RSUs are generally granted based upon a percentage of the participant's base salary. The units have a three -year vesting schedule and vest in one-third increments over the three -year period. In all circumstances, RSUs granted by AES do not entitle the holder the right, or obligate AES, to settle the RSU in cash or other assets of AES. For the years ended December 31, 2017 , 2016 , and 2015 , RSUs issued had a grant date fair value equal to the closing price of the Company's stock on the grant date. The Company does not discount the grant date fair values to reflect any post-vesting restrictions. RSUs granted to employees during the years ended December 31, 2017 , 2016 , and 2015 had grant date fair values per RSU of $11.93 , $9.42 and $12.03 , respectively. The following table summarizes the components of the Company's stock-based compensation related to its employee RSUs recognized in the Company's consolidated financial statements (in millions): December 31, 2017 2016 2015 RSU expense before income tax $ 17 $ 14 $ 13 Tax benefit (4 ) (4 ) (3 ) RSU expense, net of tax $ 13 $ 10 $ 10 Total value of RSUs converted (1) $ 10 $ 7 $ 16 Total fair value of RSUs vested $ 15 $ 13 $ 12 _____________________________ (1) Amount represents fair market value on the date of conversion. Cash was not used to settle RSUs or compensation cost capitalized as part of the cost of an asset for the years ended December 31, 2017 , 2016 , and 2015 . As of December 31, 2017 , total unrecognized compensation cost related to RSUs of $17 million is expected to be recognized over a weighted average period of approximately 1.8 years. There were no modifications to RSU awards during the year ended December 31, 2017 . A summary of the activity of RSUs for the year ended December 31, 2017 follows (RSUs in thousands): RSUs Weighted Average Grant Date Fair Values Weighted Average Remaining Vesting Term Non-vested at December 31, 2016 3,037 $ 10.70 Vested (1,337 ) 11.37 Forfeited and expired (280 ) 10.94 Granted 1,546 11.93 Non-vested at December 31, 2017 2,966 $ 11.02 1.4 Vested and expected to vest at December 31, 2017 2,711 $ 11.01 The Company initially recognizes compensation cost on the estimated number of instruments for which the requisite service is expected to be rendered. In 2017 , AES has estimated a weighted average forfeiture rate of 10.35% for RSUs granted in 2017 . This estimate will be revised if subsequent information indicates that the actual number of instruments forfeited is likely to differ from previous estimates. Based on the estimated forfeiture rate, the Company expects to expense $17 million on a straight-line basis over a three -year period. The following table summarizes the RSUs that vested and were converted during the periods indicated (RSUs in thousands): Year Ended December 31, 2017 2016 2015 RSUs vested during the year 1,337 1,063 954 RSUs converted during the year, net of shares withheld for taxes 865 705 1,238 Shares withheld for taxes 472 358 549 OTHER SHARE BASED COMPENSATION The Company has three other share-based award programs. The Company has recorded expenses of $8 million , $10 million and $8 million for 2017, 2016 and 2015, respectively, related to these programs. Stock options — AES grants options to purchase shares of common stock under stock option plans to employees and non-employee directors. Under the terms of the plans, the Company may issue options to purchase shares of the Company's common stock at a price equal to 100% of the market price at the date the option is granted. Stock options issued in 2015 have a three -year vesting schedule and vest in one-third increments over the three -year period. The stock options have a contractual term of ten years. In all circumstances, stock options granted by AES do not entitle the holder the right, or obligate AES, to settle the stock option in cash or other assets of AES. Performance Stock Units — In 2015, 2016 and 2017, the Company issued performance stock units ("PSUs") to officers under its long-term compensation plan. PSUs are restricted stock units; certain units awarded include a market condition and the remaining awards include performance conditions. Performance conditions are based on Company's Adjusted EBITDA targets for 2015 and Free Cash Flow targets for 2016 and 2017. For the units subject to market conditions, the total stockholder return on AES common stock must exceed the total stockholder return of the Standard and Poor's 500 Utilities Sector Index over a three-year measurement period. The market and performance conditions determine the vesting and final share equivalent per PSU and can result in earning an award payout range of 0% to 200% , depending on the achievement. The Company believes that it is probable that the performance condition will be met and will continue to be evaluated throughout the performance period. In all circumstances, PSUs granted by AES do not entitle the holder the right, or obligate AES, to settle the RSU in cash or other assets of AES. Performance Cash Units — In 2016 and 2017, the Company issued Performance Cash Units ("PCUs") to its officers under its long-term compensation plan. The value of these units depends on the total stockholder return on AES common stock as compared to the total stockholder return of the Standard and Poor's 500 Utilities Sector Index, Standard and Poor's 500 Index and MSCI Emerging Market Index over a three -year measurement period. Since PCUs are settled in cash, they qualify for liability accounting and periodic measurement is required.

Redeemable Stock of Subsidiarie

Redeemable Stock of Subsidiaries	12 Months Ended
	Dec. 31, 2017
Temporary Equity [Abstract]
REDEEMABLE STOCK OF SUBSIDIARES	REDEEMABLE STOCK OF SUBSIDIARIES The following table is a reconciliation of changes in redeemable stock of subsidiaries (in millions): December 31, 2017 2016 Balance at the beginning of the period $ 782 $ 538 Sale of redeemable stock of subsidiaries — 134 Contributions from holders of redeemable stock of subsidiaries 50 130 Net loss attributable to redeemable stock of subsidiaries (14 ) (11 ) Fair value adjustment (1) 25 4 Other comprehensive income (loss) attributable to redeemable stock of subsidiaries (2 ) 6 Acquisition and reclassification of stock of subsidiaries (4 ) (19 ) Balance at the end of the period $ 837 $ 782 _____________________________ (1) $5 million increase in fair value of DP&L preferred shares offset by $1 million decrease in fair value of Colon common stock in 2016. The following table summarizes the Company's redeemable stock of subsidiaries balances as of the periods indicated (in millions): December 31, 2017 2016 IPALCO common stock $ 618 $ 618 Colon quotas (1) 159 100 IPL preferred stock 60 60 Other common stock — 4 Total redeemable stock of subsidiaries $ 837 $ 782 _____________________________ (1) Characteristics of quotas are similar to common stock. Colon — Our partner in Colon made capital contributions of $50 million and $106 million during the year ended December 31, 2017 and 2016 , respectively. Any subsequent adjustments to allocate earnings and dividends to our partner, or measure the investment at fair value, will be classified as temporary equity each reporting period as it is probable that the shares will become redeemable. IPL — IPL had $60 million of cumulative preferred stock outstanding at December 31, 2017 and 2016 , which represent five series of preferred stock. The total annual dividend requirements were approximately $3 million at December 31, 2017 and 2016 . Certain series of the preferred stock were redeemable solely at the option of the issuer at prices between $100 and $118 per share. Holders of the preferred stock are entitled to elect a majority of IPL's board of directors if IPL has not paid dividends to its preferred stockholders for four consecutive quarters. Based on the preferred stockholders' ability to elect a majority of IPL's board of directors in this circumstance, the redemption of the preferred shares is considered to be not solely within the control of the issuer and the preferred stock is considered temporary equity. DPL — DPL had $18 million of cumulative preferred stock outstanding as of December 31, 2015, for which redemption became probable in September 2016. As such, the Company recorded an adjustment of $5 million to retained earnings to adjust the preferred shares to their redemption value of $23 million . In October 2016, DPL redeemed all of its preferred shares. Upon redemption, the preferred shares were no longer outstanding and all rights of the shareholders of DPL ceased to exist. IPALCO — In February 2015, CDPQ purchased 15% of AES US Investment, Inc., a wholly-owned subsidiary of IPALCO, for $247 million , with an option to invest an additional $349 million in IPALCO through 2016 in exchange for a 17.65% equity stake. In April 2015, CDPQ invested an additional $214 million in IPALCO, which resulted in CDPQ's combined direct and indirect interest in IPALCO of 24.90% . As a result of these transactions, $84 million in taxes and transaction costs were recognized as a net decrease to equity. The Company also recognized an increase to additional paid-in-capital and a reduction to retained earnings of $377 million for the excess of the fair value of the shares over their book value. No gain or loss was recognized in net income as the transaction was not considered to be a sale of in-substance real estate. In March 2016, CDPQ exercised its remaining option by investing $134 million in IPALCO, which resulted in CDPQ's combined direct and indirect interest in IPALCO of 30% . The Company also recognized an increase to additional paid-in-capital and a reduction to retained earnings of $84 million for the excess of the fair value of the shares over their book value. In June 2016, CDPQ contributed an additional $24 million to IPALCO, with no impact to the ownership structure of the investment. Any subsequent adjustments to allocate earnings and dividends to CDPQ will be classified as NCI within permanent equity as it is not probable that the shares will become redeemable.

Other Income and Expense

Other Income and Expense	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
OTHER INCOME AND EXPENSE	OTHER INCOME AND EXPENSE Other Income — Other income generally includes gains on asset sales and liability extinguishments, favorable judgments on contingencies, gains on contract terminations, allowance for funds used during construction and other income from miscellaneous transactions. The components are summarized as follows (in millions): Year Ended December 31, 2017 2016 2015 Legal settlements (1) $ 60 $ — $ — Allowance for funds used during construction (US Utilities) 26 29 17 Gain on sale of assets 1 4 17 Contract termination — — 20 Other 33 31 30 Total other income $ 120 $ 64 $ 84 _____________________________ (1) In December 2016, the Company and YPF entered into a settlement in which all parties agreed to give up any and all legal action related to gas supply contracts that were terminated in 2008 and have been in dispute since 2009. In January 2017, the YPF board approved the agreement and paid the Company $60 million, thereby resolving all uncertainties around the dispute. Other Expense — Other expense generally includes losses on asset sales and dispositions, losses on legal contingencies, and losses from other miscellaneous transactions. The components are summarized as follows (in millions): Year Ended December 31, 2017 2016 2015 Allowance for other receivables (1) $ — $ 52 $ — Loss on sale and disposal of assets 28 12 — Water rights write-off 19 6 10 Other 10 9 14 Total other expense $ 57 $ 79 $ 24 _____________________________ (1) During the fourth quarter of 2016, we recognized a full allowance on a non-trade receivable in the MCAC SBU as a result of payment delays and discussions with the counterparty. The allowance relates to certain reimbursements the Company was expecting in connection with a legal matter. Management believes the counterparty is obligated to pay and plans to continue to attempt to fully collect the non-trade receivable.

Asset Impairment Expense

Asset Impairment Expense	12 Months Ended
	Dec. 31, 2017
Impairment or Disposal of Tangible Assets Disclosure [Abstract]
ASSET IMPAIRMENT EXPENSE	ASSET IMPAIRMENT EXPENSE Year ended December 31, (in millions) 2017 2016 2015 DPL $ 175 $ 859 $ — Laurel Mountain 121 — — Kazakhstan Hydroelectric 92 — — Kazakhstan CHPs 94 — — Kilroot 37 — 121 Buffalo Gap II — 159 — Buffalo Gap I — 77 — Buffalo Gap III — — 116 U.K. Wind — — 37 Other 18 1 11 Total $ 537 $ 1,096 $ 285 Laurel Mountain — During the fourth quarter of 2017, the Company tested the recoverability of its long-lived assets at Laurel Mountain, a wind farm in the U.S. Impairment indicators were identified based on a decline in forward pricing. The Company determined that the carrying amount was not recoverable. The Laurel Mountain asset group was determined to have a fair value of $33 million using the income approach. As a result, the Company recognized an asset impairment expense of $121 million . Laurel Mountain is reported in the US SBU reportable segment. Kilroot — During the fourth quarter of 2017, the Company tested the recoverability of its long-lived assets at Kilroot, a coal and oil-fired plant in Northern Ireland, as Kilroot was not successful in bidding its coal units into the December 2017 capacity auction for the newly implemented I-SEM market. The Company determined that the carrying amount of the asset group was not recoverable. The Kilroot asset group was determined to have a fair value of $20 million using the income approach. As a result, the Company recognized an asset impairment expense of $37 million , which was limited to the carrying value of the coal units. Kilroot is reported in the Eurasia SBU reportable segment. During 2015, the Company tested the recoverability of long-lived assets at Kilroot when the regulator established lower capacity prices for the I-SEM. The Company determined that the carrying amount of the asset group was not recoverable. The Kilroot asset group was determined to have a fair value of $70 million using the income approach. As a result, the Company recognized asset impairment expense of $121 million . Kilroot is reported in the Eurasia SBU reportable segment. Kazakhstan Hydroelectric — In April 2017, the Republic of Kazakhstan stated the concession agreements would not be extended for Shulbinsk HPP and Ust-Kamenogorsk HPP, two hydroelectric plants in Kazakhstan, and initiated the process to transfer these plants back to the government. Upon meeting the held-for-sale criteria in the second quarter of 2017, the Company performed an impairment analysis and determined the carrying value of the asset group of $190 million , which included cumulative translation losses of $100 million , was greater than its fair value less costs to sell of $92 million . As a result, the Company recognized asset impairment expense of $92 million limited to the carrying value of the long-lived assets. The Company completed the transfer of the plants in October 2017. Prior to their transfer, the Kazakhstan hydroelectric plants were reported in the Eurasia SBU reportable segment. See Note 22 — Held-for-Sale Businesses and Dispositions for further information. Kazakhstan CHPs — In January 2017, the Company entered into an agreement for the sale of Ust-Kamenogorsk CHP and Sogrinsk CHP, its combined heating and power coal plants in Kazakhstan. Upon meeting the held-for-sale criteria in the first quarter of 2017, the Company performed an impairment analysis and determined that the carrying value of the asset group of $171 million , which included cumulative translation losses of $92 million , was greater than its fair value less costs to sell of $29 million . As a result, the Company recognized asset impairment expense of $94 million limited to the carrying value of the long-lived assets. The Company completed the sale of its interest in the Kazakhstan CHP plants in April 2017. Prior to their sale, the plants were reported in the Eurasia SBU reportable segment. See Note 22 — Held-for-Sale Businesses and Dispositions for further information. DPL — In March 2017, the Board of Directors of DPL approved the retirement of the DPL operated and co-owned Stuart coal-fired and diesel-fired generating units, and the Killen coal-fired generating unit and combustion turbine on or before June 1, 2018. The Company performed an impairment analysis and determined that the carrying amounts of the facilities were not recoverable. The Stuart and Killen asset groups were determined to have fair values of $3 million and $8 million , respectively, using the income approach. As a result, the Company recognized total asset impairment expense of $66 million . DPL is reported in the US SBU reportable segment. In December 2017, DPL entered into an agreement for the sale of six of its combustion turbine and diesel-fired generation facilities and related assets ("DPL peaker assets"). Upon meeting the held-for-sale criteria, the Company performed an impairment analysis and determined that the carrying value of the asset group of $346 million was greater than its fair value less costs to sell of $237 million . As a result, the Company recognized asset impairment expense of $109 million . The DPL peaker assets are reported in the US SBU reportable segment. See Note 22 — Held-for-Sale Businesses and Dispositions for further information. During the second quarter of 2016, the Company tested the recoverability of its long-lived generation assets at DPL. Uncertainty created by the Supreme Court of Ohio’s June 20, 2016 opinion regarding ESP 2, lower expectations of future revenue resulting from the most recent PJM capacity auction and higher anticipated environmental compliance costs resulting from third party studies were collectively determined to be an impairment indicator for these assets. The Company performed an impairment analysis and determined that the carrying amount of Killen, a coal-fired generation facility, and certain DPL peaking generation facilities were not recoverable. The Killen and DPL peaking generation asset groups were determined to have a fair value of $84 million and $5 million , respectively, using the income approach. As a result, the Company recognized total asset impairment expense of $235 million . DPL is reported in the US SBU reportable segment. During the fourth quarter of 2016, the Company tested the recoverability of its long-lived coal-fired generation assets and one gas-fired peaking plant at DPL. Uncertainty around the useful life of Stuart and Killen related to the Company’s ESP proceedings and lower forward dark spreads and capacity prices were collectively determined to be an impairment indicator for these assets. Market information indicating a significant decrease in the fair value of Zimmer and Miami Fort was determined to be an indicator of impairment for these assets. The lower forward dark spreads and capacity prices, along with the indicators at the other coal-fired facilities, collectively, resulted in an indicator of impairment for the Conesville asset group. For the gas-fired peaking plant, significant incremental capital expenditures relative to its fair value, and an impairment charge taken at this facility in the second quarter of 2016, were collectively determined to be impairment indicators for this asset. The Company performed an impairment analysis for each of these asset groups and determined that their carrying amounts were not recoverable. The Stuart, Killen, Miami Fort, Zimmer, Conesville and the gas-fired peaking plant asset groups were determined to have fair values of $57 million , $43 million , $36 million , $24 million , $1 million and $2 million , respectively, using the market approach for Miami Fort and Zimmer and the income approach for the remaining asset groups. As a result, the Company recognized total asset impairment expense of $624 million . DPL is reported in the US SBU reportable segment. Buffalo Gap I — During 2016, the Company tested the recoverability of its long-lived assets at Buffalo Gap I. Low wind production during 2016 resulted in management lowering future expectations of production and therefore future forecasted revenues. As such this was determined to be an impairment indicator. The Company determined that the carrying amount of the asset group was not recoverable. The Buffalo Gap I asset group was determined to have a fair value of $36 million using the income approach. As a result, the Company recognized asset impairment expense of $77 million ( $23 million attributable to AES). Buffalo Gap I is reported in the US SBU reportable segment. Buffalo Gap II — During 2016, the Company tested the recoverability of its long-lived assets at Buffalo Gap II. Impairment indicators were identified based on a decline in forward power curves. The Company determined that the carrying amount was not recoverable. The Buffalo Gap II asset group was determined to have a fair value of $92 million using the income approach. As a result, the Company recognized asset impairment expense of $159 million ( $49 million attributable to AES). Buffalo Gap II is reported in the US SBU reportable segment. Buffalo Gap III — During 2015, the Company tested the recoverability of its long-lived assets at Buffalo Gap III, a wind farm in Texas. Impairment indicators were identified based on a decline in forward power curves coupled with the near term expiration of favorable contracted cash flows. The Company determined that the carrying amount was not recoverable. The Buffalo Gap III asset group was determined to have a fair value of $118 million using the income approach. As a result, the Company recognized asset impairment expense of $116 million . Buffalo Gap III is reported in the US SBU reportable segment. U.K. Wind — During 2015, the Company decided to no longer pursue two wind projects in the U.K. based on regulatory clarifications specific to these projects, resulting in a full impairment. Impairment indicators were also identified at four other wind projects based on their current development status and a reassessment of the likelihood that each project would be pursued given aviation concerns, regulatory changes, economic considerations and other factors. The Company determined that the carrying amounts of each of these asset groups, which totaled $38 million , were not recoverable. In aggregate, the asset groups were determined to have a fair value of $1 million using the market approach and, as a result, the Company recognized asset impairment expense of $37 million . The U.K. Wind Projects are reported in the Eurasia SBU reportable segment. See Note 22 — Held-for-Sale Businesses and Dispositions for further information.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES U.S. Tax Reform — On December 22, 2017, the U.S. enacted the Tax Cuts and Jobs Act (the “2017 Act”). The 2017 Act significantly changes U.S. corporate income tax law. Among other changes effective in 2017, the 2017 Act requires companies to pay a one-time tax on certain unrepatriated earnings of foreign subsidiaries. The Company recognized the income tax effects of the 2017 Act in accordance with Staff Accounting Bulletin No. 118 (“SAB 118”) which provides SEC guidance on the application of ASC 740, Income Taxes , in the reporting period in which the 2017 Act was signed into law. Accordingly, the Company’s financial statements reflect provisional amounts for those impacts for which the accounting under ASC 740 is incomplete, but a reasonable estimate could be determined. The Company has calculated its best estimate of the impact of the 2017 Act in its income tax provision for the year ended December 31, 2017 in accordance with its understanding of the 2017 Act and guidance available as of the date of this filing, and as a result recognized $714 million of tax expense in the fourth quarter of 2017. This total includes a provisional tax expense of $39 million related to the remeasurement of certain deferred tax assets and liabilities from 35% to 21% . The most material deferred taxes to be remeasured related to net operating losses (after reduction for the one-time transition tax) and property, plant and equipment. Additional time is required to finalize remeasurement effects. In accordance with U.S. GAAP, the remeasurement of deferred tax assets and liabilities related to regulated utilities was recorded as a regulatory liability. The fourth quarter impact also includes provisional tax expense of $675 million related to the one-time transition tax on the deemed repatriation of foreign earnings. The calculation of the one-time tax is quite complex, requiring determinations of liquid asset balances over three years, determination of foreign earnings and profits (“E&P," a U.S. tax measure) at multiple dates, and multiple other computations. Our estimated tax expense was impacted by cash and restricted cash balances at foreign subsidiaries, unbilled receivables, and other liquid assets taxable at a 15.5% rate and the balance of non-cash E&P taxable at 8% . We anticipate further guidance on the determination of fair value for federal tax purposes of the shares we hold in our publicly traded subsidiaries, which are considered components of our foreign subsidiaries' "cash position" and taxed at the 15.5% rate, and may materially impact our provisional estimate. The one-time transition tax had a significant impact on our 2017 effective tax rate and utilized approximately $1.9 billion or 51% of our U.S. net operating losses. The ultimate impact may differ from these provisional amounts, possibly materially, due to, among other things, additional analysis, changes in interpretations and assumptions the Company has made, additional regulatory guidance that may be issued, and actions the Company may take as a result of the 2017 Act. The accounting is expected to be complete when the 2017 U.S. corporate income tax return is filed in 2018. Argentine Tax Reform — In December 2017, the Argentine government enacted reforms to its income tax laws that resulted in a decrease to statutory income tax rates for our Argentine businesses from 35% to 30% in 2018-2019 and to 25% for 2020 and future years. The impact of remeasuring deferred taxes to account for the enacted change in future applicable income tax rates was recognized as income tax benefit in the fourth quarter of 2017, resulting in a decrease of $21 million to consolidated income tax expense. Chilean Tax Reform — In February 2016, the Chilean government enacted further reforms to its income tax laws that resulted in an increase to statutory income tax rates for most of our Chilean businesses from 25% to 25.5% in 2017 and to 27% for 2018 and future years. The impact of remeasuring deferred taxes to account for the enacted change in future applicable income tax rates was recognized as a discrete income tax expense in the first quarter of 2016, resulting in an increase of $26 million to consolidated income tax expense. Income Tax Provision — The following table summarizes the expense for income taxes on continuing operations for the periods indicated (in millions): December 31, 2017 2016 2015 Federal: Current $ — $ 2 $ 9 Deferred 545 (361 ) (63 ) State: Current — 1 1 Deferred 1 (4 ) (5 ) Foreign: Current 335 318 470 Deferred 109 76 — Total $ 990 $ 32 $ 412 Effective and Statutory Rate Reconciliation — The following table summarizes a reconciliation of the U.S. statutory federal income tax rate to the Company's effective tax rate as a percentage of income from continuing operations before taxes for the periods indicated: December 31, 2017 2016 2015 Statutory Federal tax rate 35 % 35 % 35 % State taxes, net of Federal tax benefit (7 )% (18 )% (6 )% Taxes on foreign earnings — % (46 )% 5 % Valuation allowance 10 % 10 % (5 )% Uncertain tax positions — % 4 % (1 )% Noncontrolling Interest on Buffalo Gap impairments — % 31 % 3 % Change in tax law 90 % 12 % — % Goodwill impairment — % — % 11 % Other—net — % (11 )% — % Effective tax rate 128 % 17 % 42 % For 2017, the 90% change in tax law item relates primarily to the impact of U.S. and Argentina tax reform enacted in the current period. The impact of the U.S one-time transition tax and remeasurement of deferred taxes represents 88% and 5% , respectively, which is partially offset by the tax benefit resulting from Argentina tax reform representing 3% . For 2016 , the 31% Buffalo Gap impairments item relates to the amounts of impairment allocated to noncontrolling interest which is nondeductible. Income Tax Receivables and Payables — The current income taxes receivable and payable are included in Other Current Assets and Accrued and Other Liabilities , respectively, on the accompanying Consolidated Balance Sheets. The noncurrent income taxes receivable and payable are included in Other Noncurrent Assets and Other Noncurrent Liabilities, respectively, on the accompanying Consolidated Balance Sheets. The following table summarizes the income taxes receivable and payable as of the periods indicated (in millions): December 31, 2017 2016 Income taxes receivable—current $ 147 $ 136 Total income taxes receivable $ 147 $ 136 Income taxes payable—current $ 129 $ 149 Income taxes payable—noncurrent 17 22 Total income taxes payable $ 146 $ 171 Deferred Income Taxes — Deferred income taxes reflect the net tax effects of (a) temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes and (b) operating loss and tax credit carryforwards. These items are stated at the enacted tax rates that are expected to be in effect when taxes are actually paid or recovered. As of December 31, 2017 , the Company had federal net operating loss carryforwards for tax purposes of approximately $1.9 billion expiring in years 2027 to 2036. The Company also had federal general business tax credit carryforwards of approximately $21 million expiring primarily from 2021 to 2037, and federal alternative minimum tax credits of approximately $5 million that may be fully recovered by 2021 under the 2017 Act. The Company had state net operating loss carryforwards as of December 31, 2017 of approximately $9.3 billion expiring in years 2018 to 2037. As of December 31, 2017 , the Company had foreign net operating loss carryforwards of approximately $2.8 billion that expire at various times beginning in 2018 and some of which carry forward without expiration, and tax credits available in foreign jurisdictions of approximately $28 million , $18 million of which expire in 2021, $1 million of which expire in years 2023 to 2028, and $9 million of which carry forward without expiration. Valuation allowances increased $112 million during 2017 to $988 million at December 31, 2017 . This net increase was primarily the result of valuation allowance activity at certain of our Brazil subsidiaries. Valuation allowances decreased $18 million during 2016 to $876 million at December 31, 2016 . This net decrease was primarily the result of valuation allowance releases and foreign exchange gains at certain of our Brazil subsidiaries. The Company believes that it is more likely than not that the net deferred tax assets as shown below will be realized when future taxable income is generated through the reversal of existing taxable temporary differences and income that is expected to be generated by businesses that have long-term contracts or a history of generating taxable income. The following table summarizes deferred tax assets and liabilities, as of the periods indicated (in millions): December 31, 2017 2016 Differences between book and tax basis of property $ (1,424 ) $ (1,926 ) Other taxable temporary differences (143 ) (335 ) Total deferred tax liability (1,567 ) (2,261 ) Operating loss carryforwards 1,439 2,088 Capital loss carryforwards 63 59 Bad debt and other book provisions 66 96 Tax credit carryforwards 51 54 Other deductible temporary differences 60 263 Total gross deferred tax asset 1,679 2,560 Less: valuation allowance (988 ) (876 ) Total net deferred tax asset 691 1,684 Net deferred tax (liability) $ (876 ) $ (577 ) The Company considers undistributed earnings of certain foreign subsidiaries to be indefinitely reinvested outside of the U.S. Except for the one-time transition tax in the U.S., no taxes have been recorded with respect to our indefinitely reinvested earnings in accordance with the relevant accounting guidance for income taxes. Should the earnings be remitted as dividends, the Company may be subject to additional foreign withholding and state income taxes. Under the 2017 Act, generally future distributions from foreign subsidiaries will be subject to a dividends received deduction in the U.S. As of December 31, 2017, the cumulative amount of U.S. GAAP foreign un-remitted earnings upon which additional income taxes have not been provided is approximately $4 billion . It is not practicable to estimate the amount of any additional taxes which may be payable on the undistributed earnings. Income from operations in certain countries is subject to reduced tax rates as a result of satisfying specific commitments regarding employment and capital investment. The Company's income tax benefits related to the tax status of these operations are estimated to be $26 million , $20 million and $21 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. The per share effect of these benefits after noncontrolling interests was $0.03 , $0.02 and $0.02 for the years ended December 31, 2017 , 2016 and 2015 , respectively. Included in the Company's income tax benefits is the benefit related to our operations in Vietnam, which is estimated to be $13 million , $15 million and $8 million for the years ended December 31, 2017, 2016 and 2015, respectively. The per share effect of these benefits related to our operations in Vietnam after noncontrolling interest was $0.01 , $0.01 and $0.01 for the years ended December 31, 2017, 2016 and 2015, respectively. The following table shows the income (loss) from continuing operations, before income taxes, net equity in earnings of affiliates and noncontrolling interests, for the periods indicated (in millions): December 31, 2017 2016 2015 U.S. $ (511 ) $ (1,305 ) $ (612 ) Non-U.S. 1,282 1,492 1,601 Total $ 771 $ 187 $ 989 Uncertain Tax Positions — Uncertain tax positions have been classified as noncurrent income tax liabilities unless they are expected to be paid in one year. The Company's policy for interest and penalties related to income tax exposures is to recognize interest and penalties as a component of the provision for income taxes in the Consolidated Statements of Operations. The following table shows the total amount of gross accrued income taxes related to interest and penalties included in the Consolidated Balance Sheets for the periods indicated (in millions): December 31, 2017 2016 Interest related $ 7 $ 6 Penalties related — — The following table shows the expense/(benefit) related to interest and penalties on unrecognized tax benefits for the periods indicated (in millions): December 31, 2017 2016 2015 Total expense (benefit) for interest related to unrecognized tax benefits $ 1 $ 2 $ (2 ) Total expense for penalties related to unrecognized tax benefits — — — We are potentially subject to income tax audits in numerous jurisdictions in the U.S. and internationally until the applicable statute of limitations expires. Tax audits by their nature are often complex and can require several years to complete. The following is a summary of tax years potentially subject to examination in the significant tax and business jurisdictions in which we operate: Jurisdiction Tax Years Subject to Examination Argentina 2011-2017 Brazil 2012-2017 Chile 2014-2017 Colombia 2015-2017 Dominican Republic 2015-2017 El Salvador 2014-2017 Netherlands 2014-2017 Philippines 2013-2017 United Kingdom 2012-2017 United States (Federal) 2014-2017 As of December 31, 2017 , 2016 and 2015 , the total amount of unrecognized tax benefits was $348 million , $352 million and $364 million , respectively. The total amount of unrecognized tax benefits that would benefit the effective tax rate as of December 31, 2017 , 2016 and 2015 is $332 million , $332 million and $343 million , respectively, of which $29 million , $24 million and $24 million , respectively, would be in the form of tax attributes that would warrant a full valuation allowance. The total amount of unrecognized tax benefits anticipated to result in a net decrease to unrecognized tax benefits within 12 months of December 31, 2017 is estimated to be between $5 million and $15 million , primarily relating to statute of limitation lapses and tax exam settlements. The following is a reconciliation of the beginning and ending amounts of unrecognized tax benefits for the periods indicated (in millions): December 31, 2017 2016 2015 Balance at January 1 $ 352 $ 364 $ 384 Additions for current year tax positions — 2 2 Additions for tax positions of prior years 2 1 12 Reductions for tax positions of prior years (5 ) (1 ) (7 ) Effects of foreign currency translation — — (3 ) Settlements — (13 ) (17 ) Lapse of statute of limitations (1 ) (1 ) (7 ) Balance at December 31 $ 348 $ 352 $ 364 The Company and certain of its subsidiaries are currently under examination by the relevant taxing authorities for various tax years. The Company regularly assesses the potential outcome of these examinations in each of the taxing jurisdictions when determining the adequacy of the amount of unrecognized tax benefit recorded. While it is often difficult to predict the final outcome or the timing of resolution of any particular uncertain tax position, we believe we have appropriately accrued for our uncertain tax benefits. However, audit outcomes and the timing of audit settlements and future events that would impact our previously recorded unrecognized tax benefits and the range of anticipated increases or decreases in unrecognized tax benefits are subject to significant uncertainty. It is possible that the ultimate outcome of current or future examinations may exceed our provision for current unrecognized tax benefits in amounts that could be material, but cannot be estimated as of December 31, 2017 . Our effective tax rate and net income in any given future period could therefore be materially impacted.

Discontinued Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2017
Discontinued Operations and Disposal Groups [Abstract]
DISCONTINUED OPERATIONS AND HELD-FOR-SALE BUSINESSES	DISCONTINUED OPERATIONS Due to a portfolio evaluation in the first half of 2016, management decided to pursue a strategic shift of its distribution companies in Brazil, Sul and Eletropaulo, to reduce the Company's exposure to the Brazilian distribution market. Eletropaulo — In November 2017, Eletropaulo converted its preferred shares into ordinary shares and transitioned the listing of those shares into the Novo Mercado, which is a listing segment of the Brazilian stock exchange with the highest standards of corporate governance. Upon conversion of the preferred shares into ordinary shares, AES no longer controlled Eletropaulo, but maintained significant influence over the business. As a result, the Company deconsolidated Eletropaulo. After deconsolidation, the Company's 17% ownership interest is reflected as an equity method investment. The Company recorded an after-tax loss on deconsolidation of $611 million , which primarily consisted of $455 million related to cumulative translation losses and $243 million related to pension losses reclassified from AOCL. In December 2017, all the remaining criteria were met for Eletropaulo to qualify as a discontinued operation. Therefore, its results of operations and financial position were reported as such in the consolidated financial statements for all periods presented. Eletropaulo's pre-tax loss attributable to AES, including the loss on deconsolidation, for the years ended December 31, 2017 and 2016 was $633 million and $192 million , respectively. Eletropaulo's pre-tax income attributable to AES for the year ended December 31, 2015 was $73 million . Prior to its classification as discontinued operations, Eletropaulo was reported in the Brazil SBU reportable segment. Sul — The Company executed an agreement for the sale of Sul, a wholly-owned subsidiary, in June 2016. The results of operations and financial position of Sul are reported as discontinued operations in the consolidated financial statements for all periods presented. Upon meeting the held-for-sale criteria, the Company recognized an after-tax loss of $382 million comprised of a pre-tax impairment charge of $783 million , offset by a tax benefit of $266 million related to the impairment of the Sul long lived assets and a tax benefit of $135 million for deferred taxes related to the investment in Sul. Prior to the impairment charge, the carrying value of the Sul asset group of $1.6 billion was greater than its approximate fair value less costs to sell. However, the impairment charge was limited to the carrying value of the long lived assets of the Sul disposal group. On October 31, 2016 , the Company completed the sale of Sul and received final proceeds less costs to sell of $484 million , excluding contingent consideration. Upon disposal of Sul, the Company incurred an additional after-tax loss on sale of $737 million . The cumulative impact to earnings of the impairment and loss on sale was $1.1 billion . This includes the reclassification of approximately $1 billion of cumulative translation losses resulting in a net reduction to the Company’s stockholders’ equity of $92 million . Sul’s pre-tax loss attributable to AES for the years ended December 31, 2016 and 2015 was $1.4 billion and $32 million , respectively. Prior to its classification as discontinued operations, Sul was reported in the Brazil SBU reportable segment. The following table summarizes the carrying amounts of the major classes of assets and liabilities of discontinued operations at December 31, 2017 and December 31, 2016 : (in millions) December 31, 2017 December 31, 2016 Assets of discontinued operations and held-for-sale businesses: Cash and cash equivalents $ — $ 61 Short-term investments — 268 Accounts receivable, net of allowance for doubtful accounts of $0 and $94, respectively — 745 Other current assets — 499 Property, plant and equipment and intangibles, net — 2,504 Investments in and advances to affiliates (1) 86 — Deferred income taxes — 554 Other classes of assets that are not major — 305 Total assets of discontinued operations $ 86 $ 4,936 Other assets of businesses classified as held-for-sale (2) 1,948 — Total assets of discontinued operations and held-for-sale businesses (3) $ 2,034 $ 4,936 Liabilities of discontinued operations and held-for-sale businesses: Accounts payable $ — $ 418 Accrued and other liabilities — 954 Non-recourse debt — 1,009 Pension and other postretirement liabilities — 1,159 Other noncurrent liabilities — 678 Other classes of liabilities that are not major — 31 Total liabilities of discontinued operations $ — $ 4,249 Other liabilities of businesses classified as held-for-sale (2) 1,033 — Total liabilities of discontinued operations and held-for-sale businesses (3) $ 1,033 $ 4,249 _____________________________ (1) Represents the Company's 17% ownership interest in Eletropaulo. (2) Masinloc, Eletrica Santiago, and the DPL peaker assets were classified as held-for-sale as of December 31, 2017 . See Note 22 — Held-for-Sale Businesses and Dispositions for further information. (3) Amounts at December 31, 2016 are classified as both current and long-term on the Consolidated Balance Sheet. The following table summarizes the major line items constituting losses from discontinued operations for the periods indicated (in millions): December 31, 2017 2016 2015 Income (loss) from discontinued operations, net of tax: Revenue — regulated $ 3,320 $ 4,036 $ 4,430 Cost of sales (3,151 ) (3,954 ) (4,227 ) Other income and expense items that are not major (1) (166 ) (160 ) (70 ) Income (loss) from operations of discontinued businesses 3 (78 ) 133 Loss from disposal and impairments of discontinued businesses (611 ) (1,385 ) — Income (loss) from discontinued operations (608 ) (1,463 ) 133 Less: Net income attributable to noncontrolling interests (25 ) (142 ) (92 ) Income (loss) from discontinued operations attributable to The AES Corporation (633 ) (1,605 ) 41 Income tax benefit (expense) (21 ) 495 (53 ) Loss from discontinued operations, net of tax $ (654 ) $ (1,110 ) $ (12 ) _____________________________ (1) Includes a loss contingency recognized by our equity method investment in discontinued operations. The following table summarizes the operating and investing cash flows from discontinued operations for the periods indicated (in millions): December 31, 2017 2016 2015 Cash flows provided by (used in) operating activities of discontinued operations $ 164 $ 529 $ (125 ) Cash flows used in investing activities of discontinued operations (288 ) (368 ) (65 )

Acquisitions and Dispositions

Acquisitions and Dispositions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
ACQUISITIONS AND DISPOSITIONS	Held-for-Sale Businesses Masinloc — In December 2017, the Company entered into an agreement to sell its entire 51% equity interest in Masinloc for approximately $1 billion , subject to customary purchase price adjustments. Masinloc consists of a coal-fired generation plant in operation, a coal-fired generation plant currently under construction, and an energy storage facility all located in the Philippines. Closing of the sale is expected during the first half of 2018, subject to certain regulatory approvals. As of December 31, 2017 , Masinloc was classified as held-for-sale, but did not meet the criteria to be reported as discontinued operations. On a consolidated basis, the net carrying value of Masinloc at December 31, 2017 was $475 million . Masinloc is reported in the Eurasia SBU reportable segment. In 2014, the Company completed the sale of 45% of its ownership interest in Masinloc for $436 million , including $23 million of consideration that was contingent upon the achievement of certain tax restructuring efficiencies. The transaction was accounted for as a sale of in-substance real estate. In December 2017, the related contingency expired and the $23 million of contingent consideration was recognized as a gain in Gain (loss) on disposal and sale of bus inesses in the Consolidated Statement of Operations. Electrica Santiago — In December 2017, AES Gener entered into an agreement to sell Electrica Santiago, comprised of four gas and diesel-fired generation plants in Chile, for $300 million , subject to customary purchase price adjustments. The sale is expected to close during the first half of 2018, subject to conditions precedent in the agreement. As of December 31, 2017 , Electrica Santiago was classified as held-for-sale, but did not meet the criteria to be reported as discontinued operations. Electrica Santiago's carrying value at December 31, 2017 was $186 million . Electrica Santiago is reported in the Andes SBU reportable segment. DPL Peaker Assets — In December 2017, DPL entered into an agreement to sell six of its combustion turbine and diesel-fired generation facilities and related assets ("DPL peaker assets") for $241 million , subject to purchase price adjustments. The sale is subject to regulatory approvals, and is expected to close in the first half of 2018. As of December 31, 2017 , the DPL peaker assets were classified as held-for-sale but did not meet the criteria to be reported as discontinued operations. After impairment, the net carrying value of the DPL peaker assets at December 31, 2017 was $237 million . The DPL peaker assets are reported in the US SBU reportable segment. See Note 19 — Asset Impairment Expense for further information. Excluding any impairment charges or gain/loss on sale, pre-tax income attributable to AES of businesses held-for-sale as of December 31, 2017 was as follows (in millions): Year Ended December 31, 2017 2016 2015 Masinloc $ 103 $ 103 $ 99 Electrica Santiago 9 11 10 DPL Peaker Assets 17 20 24 Total $ 129 $ 134 $ 133 Dispositions Zimmer and Miami Fort — In December 2017, DPL and AES Ohio Generation completed the sale of Zimmer and Miami Fort, two coal-fired generating plants, for net proceeds of $70 million , resulting in a gain on sale of $13 million . The sale did not meet the criteria to be reported as discontinued operations. Prior to their sale, Zimmer and Miami Fort were reported in the US SBU reportable segment. Kazakhstan Hydroelectric — Affiliates of the Company (the “Affiliates”) previously operated Shulbinsk HPP and Ust-Kamenogorsk HPP (the “HPPs”), two hydroelectric plants in Kazakhstan, under a concession agreement with the Republic of Kazakhstan (“RoK”). In April 2017, the RoK initiated the process to transfer these plants back to the RoK. The RoK indicated that arbitration would be necessary to determine the correct Return Share Transfer Payment ("RST") and, rather than paying the Affiliates, deposited the RST into an escrow account. In exchange, the Affiliates transferred 100% of the shares in the HPPs to the RoK, under protest and with a full reservation of rights. The Company recorded a loss on disposal of $33 million in the fourth quarter of 2017. In February 2018, the Affiliates initiated the arbitration process in international court to recover at least $75 million of the RST placed in escrow, based on the September 30, 2017 RST calculation. Additional losses may be incurred if some or all of the disputed consideration is not paid by the RoK via a mutually acceptable settlement, or upon any unfavorable decision rendered by the arbiter. The transfer did not meet the criteria to be reported as discontinued operations. Prior to their transfer, the Kazakhstan HPPs were reported in the Eurasia SBU reportable segment. See Note 19 — Asset Impairment Expense for further information. Kazakhstan CHPs — In April 2017, the Company completed the sale of Ust-Kamenogorsk CHP and Sogrinsk CHP, its combined heating and power coal plants in Kazakhstan, for net proceeds of $24 million . The Company recognized a pre-tax loss on sale of $49 million , primarily related to cumulative translation losses. The sale did not meet the criteria to be reported as discontinued operations. Prior to their sale, the Kazakhstan CHP plants were reported in the Eurasia SBU reportable segment. See Note 19 — Asset Impairment Expense for further information. U.K. Wind — During the second quarter of 2016, the Company deconsolidated UK Wind and recorded a loss on deconsolidation of $20 million to Gain (loss) on disposal and sale of bus inesses in the Consolidated Statement of Operations. Prior to deconsolidation, UK Wind was reported in the Eurasia SBU reportable segment. See Note 14 — Equity and Note 19 — Asset Impairment Expense for further information. DPLER — In January 2016, the Company completed the sale of DPLER, a competitive retail marketer selling electricity to customers in Ohio, and recognized a gain on sale of $49 million . Proceeds of $76 million were received in December 2015. DPLER did not meet the criteria to be reported as a discontinued operation. DPLER's results were therefore reflected within continuing operations in the Consolidated Statements of Operations. Prior to its sale, DPLER was reported in the US SBU reportable segment. Kelanitissa — In January 2016, the Company completed the sale of its interest in Kelanitissa, a diesel-fired generation plant in Sri Lanka, for $18 million , resulting in a loss on sale of $5 million . The sale did not meet the criteria to be reported as discontinued operations. Kelanitissa's results were therefore reflected within continuing operations in the Consolidated Statements of Operations. Prior to its sale, Kelanitissa was reported in the Eurasia SBU reportable segment. Armenia Mountain — Under the terms of the sale agreement for certain U.S. Wind Projects, the buyer was provided an option to purchase the Company's 100% interest in Armenia Mountain, a wind project in Pennsylvania, for $75 million . The buyer exercised this option and AES completed the sale of Armenia Mountain in July 2015. The sale did not meet the criteria to be reported as discontinued operations. Upon completion, net proceeds of $64 million were received and a pre-tax gain on sale of $22 million was recognized. Prior to its sale, Armenia Mountain was reported in the US SBU reportable segment. ACQUISITIONS Alto Sertão II — On August 3, 2017, the Company completed the acquisition of 100% of the Alto Sertão II Wind Complex (“Alto Sertão II”) from Renova Energia S.A. for $181 million , subject to customary purchase price adjustments, plus the assumption of $348 million of non-recourse debt, and up to $30 million of contingent consideration. At closing, the Company made an initial cash payment of $143 million , which excludes holdbacks related to indemnifications and purchase price adjustments. As of December 31, 2017 , the purchase price allocation for Alto Sertão II is preliminary. The Company is in the process of assessing the fair value of the assets acquired and liabilities assumed in the acquisition, and expects to complete the purchase price allocation within the one year measurement period. Alto Sertão II is a wind farm reported in the Brazil SBU reportable segment. Bauru Solar Complex — On September 25, 2017, AES Tietê executed an investment agreement with Cobra do Brasil to provide approximately $140 million of non-convertible debentures in project financing for the construction of photovoltaic solar plants in Brazil. As of December 31, 2017 , approximately $45 million of non-convertible debentures have been executed and distributed to the project. Upon completion of the project, expected in the first half of 2018 and subject to the solar plants’ compliance with certain technical specifications defined in the agreement, Tietê expects to acquire the solar complex in exchange for the non-convertible debentures and an additional investment of approximately $55 million . Distributed Energy — On February 18, 2015, the Company completed the acquisition of 100% of the common stock of Main Street Power Company, Inc. for approximately $25 million . The purchase consideration was composed of $20 million cash. After the date of acquisition, Main Street Power Company, Inc. was renamed Distributed Energy, Inc. In September 2016, Distributed Energy acquired the equity interest of various projects held by multiple partnerships for approximately $43 million . These partnerships were previously classified as equity method investments. In accordance with the accounting guidance for business combinations, the Company has recorded the opening balance sheets of the acquired businesses based on the purchase price allocation as of the acquisition date.

Acquisitions Acquisitions

Acquisitions Acquisitions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Mergers, Acquisitions and Dispositions Disclosures [Text Block]	Held-for-Sale Businesses Masinloc — In December 2017, the Company entered into an agreement to sell its entire 51% equity interest in Masinloc for approximately $1 billion , subject to customary purchase price adjustments. Masinloc consists of a coal-fired generation plant in operation, a coal-fired generation plant currently under construction, and an energy storage facility all located in the Philippines. Closing of the sale is expected during the first half of 2018, subject to certain regulatory approvals. As of December 31, 2017 , Masinloc was classified as held-for-sale, but did not meet the criteria to be reported as discontinued operations. On a consolidated basis, the net carrying value of Masinloc at December 31, 2017 was $475 million . Masinloc is reported in the Eurasia SBU reportable segment. In 2014, the Company completed the sale of 45% of its ownership interest in Masinloc for $436 million , including $23 million of consideration that was contingent upon the achievement of certain tax restructuring efficiencies. The transaction was accounted for as a sale of in-substance real estate. In December 2017, the related contingency expired and the $23 million of contingent consideration was recognized as a gain in Gain (loss) on disposal and sale of bus inesses in the Consolidated Statement of Operations. Electrica Santiago — In December 2017, AES Gener entered into an agreement to sell Electrica Santiago, comprised of four gas and diesel-fired generation plants in Chile, for $300 million , subject to customary purchase price adjustments. The sale is expected to close during the first half of 2018, subject to conditions precedent in the agreement. As of December 31, 2017 , Electrica Santiago was classified as held-for-sale, but did not meet the criteria to be reported as discontinued operations. Electrica Santiago's carrying value at December 31, 2017 was $186 million . Electrica Santiago is reported in the Andes SBU reportable segment. DPL Peaker Assets — In December 2017, DPL entered into an agreement to sell six of its combustion turbine and diesel-fired generation facilities and related assets ("DPL peaker assets") for $241 million , subject to purchase price adjustments. The sale is subject to regulatory approvals, and is expected to close in the first half of 2018. As of December 31, 2017 , the DPL peaker assets were classified as held-for-sale but did not meet the criteria to be reported as discontinued operations. After impairment, the net carrying value of the DPL peaker assets at December 31, 2017 was $237 million . The DPL peaker assets are reported in the US SBU reportable segment. See Note 19 — Asset Impairment Expense for further information. Excluding any impairment charges or gain/loss on sale, pre-tax income attributable to AES of businesses held-for-sale as of December 31, 2017 was as follows (in millions): Year Ended December 31, 2017 2016 2015 Masinloc $ 103 $ 103 $ 99 Electrica Santiago 9 11 10 DPL Peaker Assets 17 20 24 Total $ 129 $ 134 $ 133 Dispositions Zimmer and Miami Fort — In December 2017, DPL and AES Ohio Generation completed the sale of Zimmer and Miami Fort, two coal-fired generating plants, for net proceeds of $70 million , resulting in a gain on sale of $13 million . The sale did not meet the criteria to be reported as discontinued operations. Prior to their sale, Zimmer and Miami Fort were reported in the US SBU reportable segment. Kazakhstan Hydroelectric — Affiliates of the Company (the “Affiliates”) previously operated Shulbinsk HPP and Ust-Kamenogorsk HPP (the “HPPs”), two hydroelectric plants in Kazakhstan, under a concession agreement with the Republic of Kazakhstan (“RoK”). In April 2017, the RoK initiated the process to transfer these plants back to the RoK. The RoK indicated that arbitration would be necessary to determine the correct Return Share Transfer Payment ("RST") and, rather than paying the Affiliates, deposited the RST into an escrow account. In exchange, the Affiliates transferred 100% of the shares in the HPPs to the RoK, under protest and with a full reservation of rights. The Company recorded a loss on disposal of $33 million in the fourth quarter of 2017. In February 2018, the Affiliates initiated the arbitration process in international court to recover at least $75 million of the RST placed in escrow, based on the September 30, 2017 RST calculation. Additional losses may be incurred if some or all of the disputed consideration is not paid by the RoK via a mutually acceptable settlement, or upon any unfavorable decision rendered by the arbiter. The transfer did not meet the criteria to be reported as discontinued operations. Prior to their transfer, the Kazakhstan HPPs were reported in the Eurasia SBU reportable segment. See Note 19 — Asset Impairment Expense for further information. Kazakhstan CHPs — In April 2017, the Company completed the sale of Ust-Kamenogorsk CHP and Sogrinsk CHP, its combined heating and power coal plants in Kazakhstan, for net proceeds of $24 million . The Company recognized a pre-tax loss on sale of $49 million , primarily related to cumulative translation losses. The sale did not meet the criteria to be reported as discontinued operations. Prior to their sale, the Kazakhstan CHP plants were reported in the Eurasia SBU reportable segment. See Note 19 — Asset Impairment Expense for further information. U.K. Wind — During the second quarter of 2016, the Company deconsolidated UK Wind and recorded a loss on deconsolidation of $20 million to Gain (loss) on disposal and sale of bus inesses in the Consolidated Statement of Operations. Prior to deconsolidation, UK Wind was reported in the Eurasia SBU reportable segment. See Note 14 — Equity and Note 19 — Asset Impairment Expense for further information. DPLER — In January 2016, the Company completed the sale of DPLER, a competitive retail marketer selling electricity to customers in Ohio, and recognized a gain on sale of $49 million . Proceeds of $76 million were received in December 2015. DPLER did not meet the criteria to be reported as a discontinued operation. DPLER's results were therefore reflected within continuing operations in the Consolidated Statements of Operations. Prior to its sale, DPLER was reported in the US SBU reportable segment. Kelanitissa — In January 2016, the Company completed the sale of its interest in Kelanitissa, a diesel-fired generation plant in Sri Lanka, for $18 million , resulting in a loss on sale of $5 million . The sale did not meet the criteria to be reported as discontinued operations. Kelanitissa's results were therefore reflected within continuing operations in the Consolidated Statements of Operations. Prior to its sale, Kelanitissa was reported in the Eurasia SBU reportable segment. Armenia Mountain — Under the terms of the sale agreement for certain U.S. Wind Projects, the buyer was provided an option to purchase the Company's 100% interest in Armenia Mountain, a wind project in Pennsylvania, for $75 million . The buyer exercised this option and AES completed the sale of Armenia Mountain in July 2015. The sale did not meet the criteria to be reported as discontinued operations. Upon completion, net proceeds of $64 million were received and a pre-tax gain on sale of $22 million was recognized. Prior to its sale, Armenia Mountain was reported in the US SBU reportable segment. ACQUISITIONS Alto Sertão II — On August 3, 2017, the Company completed the acquisition of 100% of the Alto Sertão II Wind Complex (“Alto Sertão II”) from Renova Energia S.A. for $181 million , subject to customary purchase price adjustments, plus the assumption of $348 million of non-recourse debt, and up to $30 million of contingent consideration. At closing, the Company made an initial cash payment of $143 million , which excludes holdbacks related to indemnifications and purchase price adjustments. As of December 31, 2017 , the purchase price allocation for Alto Sertão II is preliminary. The Company is in the process of assessing the fair value of the assets acquired and liabilities assumed in the acquisition, and expects to complete the purchase price allocation within the one year measurement period. Alto Sertão II is a wind farm reported in the Brazil SBU reportable segment. Bauru Solar Complex — On September 25, 2017, AES Tietê executed an investment agreement with Cobra do Brasil to provide approximately $140 million of non-convertible debentures in project financing for the construction of photovoltaic solar plants in Brazil. As of December 31, 2017 , approximately $45 million of non-convertible debentures have been executed and distributed to the project. Upon completion of the project, expected in the first half of 2018 and subject to the solar plants’ compliance with certain technical specifications defined in the agreement, Tietê expects to acquire the solar complex in exchange for the non-convertible debentures and an additional investment of approximately $55 million . Distributed Energy — On February 18, 2015, the Company completed the acquisition of 100% of the common stock of Main Street Power Company, Inc. for approximately $25 million . The purchase consideration was composed of $20 million cash. After the date of acquisition, Main Street Power Company, Inc. was renamed Distributed Energy, Inc. In September 2016, Distributed Energy acquired the equity interest of various projects held by multiple partnerships for approximately $43 million . These partnerships were previously classified as equity method investments. In accordance with the accounting guidance for business combinations, the Company has recorded the opening balance sheets of the acquired businesses based on the purchase price allocation as of the acquisition date.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Basic and diluted earnings per share are based on the weighted-average number of shares of common stock and potential common stock outstanding during the period. Potential common stock, for purposes of determining diluted earnings per share, includes the effects of dilutive restricted stock units, stock options and convertible securities. The effect of such potential common stock is computed using the treasury stock method or the if-converted method, as applicable. The following table is a reconciliation of the numerator and denominator of the basic and diluted earnings per share computation for income from continuing operations for the years ended December 31, 2017 , 2016 and 2015 , where income represents the numerator and weighted-average shares represent the denominator. Values are in millions except per share data: Year Ended December 31, 2017 2016 2015 Loss Shares $ per Share Loss Shares $ per Share Income Shares $ per Share BASIC EARNINGS PER SHARE Income (loss) from continuing operations attributable to The AES Corporation common stockholders (1) $ (507 ) 660 $ (0.77 ) $ (25 ) 660 $ (0.04 ) $ 318 687 $ 0.46 EFFECT OF DILUTIVE SECURITIES Restricted stock units — — — — — — — 2 — DILUTED EARNINGS PER SHARE $ (507 ) 660 $ (0.77 ) $ (25 ) 660 $ (0.04 ) $ 318 689 $ 0.46 _____________________________ (1) Loss from continuing operations, net of tax, of $20 million less the $5 million adjustment to retained earnings to record the DP&L redeemable preferred stock at its redemption value as of December 31, 2016 . The calculation of diluted earnings per share excluded 7 million , 8 million and 8 million stock awards outstanding for the years ended December 31, 2017 , 2016 and 2015 , respectively, that could potentially dilute basic earnings per share in the future. Additionally, for the years ended December 31, 2016 and 2015 , all 15 million convertible debentures were omitted from the earnings per share calculation. The Company redeemed all of its existing TECONs in June 2017. The stock awards and convertible debentures were excluded from the calculation because they were anti-dilutive.

Risks and Uncertainties

Risks and Uncertainties	12 Months Ended
	Dec. 31, 2017
Risks and Uncertainties [Abstract]
RISKS AND UNCERTAINTIES	RISKS AND UNCERTAINTIES AES is a diversified power generation and utility company organized into five market-oriented SBUs. See additional discussion of the Company's principal markets in Note 15 — Segment and Geographic Information . Within our five SBUs, we have two primary lines of business: Generation and Utilities. The Generation line of business uses a wide range of fuels and technologies to generate electricity such as coal, gas, hydro, wind, solar and biomass. Our Utilities business comprises businesses that transmit, distribute, and in certain circumstances, generate power. In addition, the Company has operations in the renewables area. These efforts include projects primarily in wind and solar. Operating and Economic Risks — The Company operates in several developing economies where macroeconomic conditions are usually more volatile than developed economies. Deteriorating market conditions often expose the Company to the risk of decreased earnings and cash flows due to, among other factors, adverse fluctuations in the commodities and foreign currency spot markets. Additionally, credit markets around the globe continue to tighten their standards, which could impact our ability to finance growth projects through access to capital markets. Currently, the Company has a below-investment grade rating from Standard & Poor's of BB-. This could affect the Company's ability to finance new and/or existing development projects at competitive interest rates. As of December 31, 2017 , the Company had $949 million of unrestricted cash and cash equivalents. During 2017 , 69% of our revenue was generated outside the U.S. and a significant portion of our international operations is conducted in developing countries. We continue to invest in several developing countries to expand our existing platform and operations. International operations, particularly the operation, financing and development of projects in developing countries, entail significant risks and uncertainties, including, without limitation: • economic, social and political instability in any particular country or region; • inability to economically hedge energy prices; • volatility in commodity prices; • adverse changes in currency exchange rates; • government restrictions on converting currencies or repatriating funds; • unexpected changes in foreign laws, regulatory framework, or in trade, monetary or fiscal policies; • high inflation and monetary fluctuations; • restrictions on imports of coal, oil, gas or other raw materials required by our generation businesses to operate; • threatened or consummated expropriation or nationalization of our assets by foreign governments; • unwillingness of governments, government agencies, similar organizations or other counterparties to honor their commitments; • unwillingness of governments, government agencies, courts or similar bodies to enforce contracts that are economically advantageous to subsidiaries of the Company and economically unfavorable to counterparties, against such counterparties, whether such counterparties are governments or private parties; • inability to obtain access to fair and equitable political, regulatory, administrative and legal systems; • adverse changes in government tax policy; • difficulties in enforcing our contractual rights, enforcing judgments, or obtaining a just result in local jurisdictions; and • potentially adverse tax consequences of operating in multiple jurisdictions. Any of these factors, individually or in combination with others, could materially and adversely affect our business, results of operations and financial condition. In addition, our Latin American operations experience volatility in revenue and earnings which have caused and are expected to cause significant volatility in our results of operations and cash flows. The volatility is caused by regulatory and economic difficulties, political instability, indexation of certain PPAs to fuel prices, and currency fluctuations being experienced in many of these countries. This volatility reduces the predictability and enhances the uncertainty associated with cash flows from these businesses. Our inability to predict, influence or respond appropriately to changes in law or regulatory schemes, including any inability to obtain reasonable increases in tariffs or tariff adjustments for increased expenses, could adversely impact our results of operations or our ability to meet publicly announced projections or analysts' expectations. Furthermore, changes in laws or regulations or changes in the application or interpretation of regulatory provisions in jurisdictions where we operate, particularly our Utility businesses where electricity tariffs are subject to regulatory review or approval, could adversely affect our business, including, but not limited to: • changes in the determination, definition or classification of costs to be included as reimbursable or pass-through costs; • changes in the definition or determination of controllable or noncontrollable costs; • adverse changes in tax law; • changes in the definition of events which may or may not qualify as changes in economic equilibrium; • changes in the timing of tariff increases; • other changes in the regulatory determinations under the relevant concessions; or • changes in environmental regulations, including regulations relating to GHG emissions in any of our businesses. Any of the above events may result in lower margins for the affected businesses, which can adversely affect our results of operations. Alto Maipo — The Company's subsidiary, AES Gener, is currently constructing Alto Maipo, a hydroelectric facility near Santiago Chile. Increased project costs, or delays in construction, at Alto Maipo could have an adverse impact on the Company. Alto Maipo has experienced construction difficulties, which have resulted in an increase in projected costs over the original $2 billion budget. These overages led to a series of negotiations with the intention of restructuring the project’s existing financial structure and obtaining additional funding. On March 17, 2017, AES Gener completed the legal and financial restructuring of Alto Maipo, and through the Company’s 67% ownership interest in AES Gener, AES now has an effective 62% indirect economic interest in Alto Maipo. See Note 14 — Equity for additional information regarding the restructuring. Following the restructuring described above, the project continued to face construction difficulties, including greater than expected costs and slower than anticipated productivity by construction contractors toward agreed-upon milestones. Furthermore, during the second quarter of 2017, as a result of the failure to perform by one of its construction contractors, Constructora Nuevo Maipo S.A. (“CNM”), Alto Maipo terminated CNM’s contract. As a result of the termination of CNM, Alto Maipo’s construction debt of $618 million and derivative liabilities of $132 million are in technical default and presented as current in the balance sheet as of December 31, 2017 . Construction at the project is continuing and the project is over 61% complete. In February 2018, Alto Maipo signed an amended EPC contract with Strabag, the permanent replacement contractor selected to complete CNM’s work, subject to approval by the project's senior lenders as part of the second refinancing. Alto Maipo is working to resolve the challenges described above, however, there can be no assurance that Alto Maipo will succeed in these efforts and if there are further delays or cost overruns, or if Alto Maipo is unable to reach an agreement with the non-recourse lenders, there is a risk these lenders may seek to exercise remedies available as a result of the default noted above, or Alto Maipo may not be able to meet its contractual or other obligations and may be unable to continue with the project. If any of the above occur, there could be a material impairment for the Company. The carrying value of the long-lived assets and deferred tax assets of Alto Maipo as of December 31, 2017 was approximately $1.4 billion and $60 million , respectively. Even though certain of the construction difficulties have not been formally resolved, construction costs continue to be capitalized as management believes the project is probable of completion. Management believes the carrying value of the long-lived asset group is recoverable and was not impaired as of December 31, 2017 . In addition, management believes it is more likely than not that the deferred tax assets will be realized, they could be reduced if estimates of future taxable income are decreased. Puerto Rico — In September 2017, Puerto Rico was severely impacted by Hurricanes Irma and Maria, disrupting the operations of AES Puerto Rico and AES Ilumina. Puerto Rico’s infrastructure was severely damaged, including electric infrastructure and transmission lines. The extensive structural damage caused by hurricane winds and flooding is expected to take considerable time to repair. The Company sustained modest damage to its AES Ilumina solar plant, resulting in a $2 million loss, and minor damage to its AES Puerto Rico thermal plants. Our subsidiaries in Puerto Rico have long-term PPAs with state-owned PREPA. As a result of the hurricanes, PREPA has declared an event of Force Majeure. However, both units of AES Puerto Rico and approximately 75% of AES Ilumina are available to generate electricity which, in accordance with the PPAs, will allow AES Puerto Rico to invoice capacity, even under Force Majeure. Due to the extensive damage from the hurricanes, energy demand in Puerto Rico has decreased and is expected to remain low until economic activity has recovered. Despite the decrease in demand, AES Puerto Rico was dispatched starting in February 2018. AES Puerto Rico continues to be the lowest cost and EPA compliant energy provider in Puerto Rico. Therefore, we expect AES Puerto Rico to continue to be a critical supplier to PREPA. Starting prior to the hurricanes, PREPA has been facing economic challenges that could impact the Company, and on July 2, 2017, filed for bankruptcy under Title III. As a result of the bankruptcy filing, AES Puerto Rico and AES Ilumina’s non-recourse debt of $365 million and $36 million , respectively, is in default and has been classified as current as of December 31, 2017 . In November 2017, AES Puerto Rico signed a Forbearance and Standstill Agreement with its lenders to prevent the lenders from taking any action against the company due to the default events. This agreement will expire on March 22, 2018. The Company's receivable balances in Puerto Rico as of December 31, 2017 totaled $86 million , of which $53 million was overdue. After the filing of Title III protection, and up until the disruption caused by the hurricanes, AES in Puerto Rico was collecting the overdue amounts from PREPA in line with historic payment patterns. Considering the information available as of the filing date, management believes the carrying amount of our assets in Puerto Rico of $627 million is recoverable as of December 31, 2017 and no reserve on the receivables is required. Foreign Currency Risks — AES operates businesses in many foreign countries and such operations could be impacted by significant fluctuations in foreign currency exchange rates. Fluctuations in currency exchange rate between U.S. dollar and the following currencies could create significant fluctuations in earnings and cash flows: the Argentine peso, the Brazilian real, the Dominican Republic peso, the Euro, the Chilean peso, the Colombian peso, and the Philippine peso. Concentrations — Due to the geographical diversity of its operations, the Company does not have any significant concentration of customers or sources of fuel supply. Several of the Company's generation businesses rely on PPAs with one or a limited number of customers for the majority of, and in some cases all of, the relevant businesses' output over the term of the PPAs. However, no single customer accounted for 10% or more of total revenue in 2017 , 2016 or 2015 . The cash flows and results of operations of our businesses depend on the credit quality of our customers and the continued ability of our customers and suppliers to meet their obligations under PPAs and fuel supply agreements. If a substantial portion of the Company's long-term PPAs and/or fuel supply were modified or terminated, the Company would be adversely affected to the extent that it would be unable to replace such contracts at equally favorable terms.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS Certain of our businesses in Panama and the Dominican Republic are partially owned by governments either directly or through state-owned institutions. In the ordinary course of business, these businesses enter into energy purchase and sale transactions, and transmission agreements with other state-owned institutions which are controlled by such governments. At two of our generation businesses in Mexico, the offtakers exercise significant influence, but not control, through representation on these businesses' Boards of Directors. These offtakers are also required to hold a nominal ownership interest in such businesses. In Chile, we provide capacity and energy under contractual arrangements to our investment which is accounted for under the equity method of accounting. Additionally, the Company provides certain support and management services to several of its affiliates under various agreements. The Company's Consolidated Statements of Operations included the following transactions with related parties for the periods indicated (in millions): Years Ended December 31, 2017 2016 2015 Revenue—Non-Regulated $ 1,297 $ 1,100 $ 1,099 Cost of Sales—Non-Regulated 220 210 330 Interest income 8 4 25 Interest expense 36 39 33 The following table summarizes the balances receivable from and payable to related parties included in the Company's Consolidated Balance Sheets as of the periods indicated (in millions): December 31, 2017 2016 Receivables from related parties $ 250 $ 218 Accounts and notes payable to related parties 727 892 The Company entered into an equity transaction with our related party, Linda Group, see Note 14 — Equity for further information.

Selected Quarterly Financial Da

Selected Quarterly Financial Data	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) Quarterly Financial Data — The following tables summarize the unaudited quarterly Condensed Consolidated Statements of Operations for the Company for 2017 and 2016 (amounts in millions, except per share data). Amounts have been restated to reflect discontinued operations in all periods presented and reflect all adjustments necessary in the opinion of management for a fair statement of the results for interim periods. Quarter Ended 2017 Mar 31 June 30 Sept 30 Dec 31 Revenue $ 2,581 $ 2,613 $ 2,693 $ 2,643 Operating margin 554 625 642 643 Income (loss) from continuing operations, net of tax (1) 97 141 236 (622 ) Income (loss) from discontinued operations, net of tax 1 9 25 (664 ) Net income (loss) $ 98 $ 150 $ 261 $ (1,286 ) Net income (loss) attributable to The AES Corporation $ (24 ) $ 53 $ 152 $ (1,342 ) Basic income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.04 $ 0.08 $ 0.22 $ (1.03 ) Income (loss) from discontinued operations attributable to The AES Corporation common stockholders, net of tax — — 0.01 (1.00 ) Basic income (loss) per share attributable to The AES Corporation $ 0.04 $ 0.08 $ 0.23 $ (2.03 ) Diluted income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.04 $ 0.08 $ 0.22 $ (1.03 ) Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax — — 0.01 (1.00 ) Diluted income (loss) per share attributable to The AES Corporation $ 0.04 $ 0.08 $ 0.23 $ (2.03 ) Dividends declared per common share $ 0.12 $ — $ 0.12 $ 0.25 Quarter Ended 2016 Mar 31 June 30 Sept 30 Dec 31 Revenue $ 2,530 $ 2,452 $ 2,639 $ 2,660 Operating margin 501 556 691 632 Income (loss) from continuing operations, net of tax (2) 87 2 238 (136 ) Loss from discontinued operations, net of tax (13 ) (389 ) (9 ) (557 ) Net income (loss) $ 74 $ (387 ) $ 229 $ (693 ) Net income (loss) attributable to The AES Corporation $ 126 $ (482 ) $ 175 $ (949 ) Basic income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.21 $ (0.15 ) $ 0.26 $ (0.35 ) Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax (0.02 ) (0.58 ) — (1.09 ) Basic income (loss) per share attributable to The AES Corporation $ 0.19 $ (0.73 ) $ 0.26 $ (1.44 ) Diluted income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.20 $ (0.15 ) $ 0.26 $ (0.35 ) Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax (0.01 ) (0.58 ) — (1.09 ) Diluted income (loss) per share attributable to The AES Corporation $ 0.19 $ (0.73 ) $ 0.26 $ (1.44 ) Dividends declared per common share $ 0.11 $ — $ 0.11 $ 0.23 _____________________________ (1) Includes pre-tax impairment expense of $168 million , $90 million , $2 million and $277 million , for the first, second, third and fourth quarters of 2017 , respectively. See Note 19 — Asset Impairment Expense for further discussion. (2) Includes pre-tax impairment expense of $159 million , $235 million , $79 million and $623 million , for the first, second, third and fourth quarters of 2016 , respectively. See Note 19 — Asset Impairment Expense for further discussion.

Subsequent Event Subsequent Eve

Subsequent Event Subsequent Events	12 Months Ended
	Dec. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Fluence — In July 2017, the Company entered into a joint venture with Siemens AG to form a global energy storage technology and services company under the name Fluence. On January 1, 2018, Siemens and AES closed on the creation of the joint venture with each party holding a 50% ownership interest. Since AES does not have the ability to control Fluence, the joint venture will be accounted for as an equity affiliate.

Schedule I - Condensed Financia

Schedule I - Condensed Financial Information of Parent	12 Months Ended
	Dec. 31, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PARENT	THE AES CORPORATION SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PARENT BALANCE SHEETS December 31, 2017 2016 (in millions) ASSETS Current Assets: Cash and cash equivalents $ 10 $ 109 Restricted cash — 3 Accounts and notes receivable from subsidiaries 143 155 Prepaid expenses and other current assets 27 39 Total current assets 180 306 Investment in and advances to subsidiaries and affiliates 8,239 7,561 Office Equipment: Cost 27 26 Accumulated depreciation (18 ) (16 ) Office equipment, net 9 10 Other Assets: Other intangible assets, net of accumulated amortization 3 5 Deferred financing costs, net of accumulated amortization of $2 and $1, respectively 5 5 Deferred income taxes 289 1,041 Other assets 2 13 Total other assets 299 1,064 Total assets $ 8,727 $ 8,941 LIABILITIES AND STOCKHOLDERS' EQUITY Current Liabilities: Accounts payable $ 18 $ 18 Accounts and notes payable to subsidiaries 381 304 Accrued and other liabilities 246 250 Senior notes payable—current portion 5 — Total current liabilities 650 572 Long-term Liabilities: Senior notes payable 4,625 4,154 Junior subordinated notes and debentures payable — 517 Accounts and notes payable to subsidiaries 967 883 Other long-term liabilities 20 21 Total long-term liabilities 5,612 5,575 Stockholders' equity: Common stock 8 8 Additional paid-in capital 8,501 8,592 Accumulated deficit (2,276 ) (1,146 ) Accumulated other comprehensive loss (1,876 ) (2,756 ) Treasury stock (1,892 ) (1,904 ) Total stockholders' equity 2,465 2,794 Total liabilities and equity $ 8,727 $ 8,941 See Notes to Schedule I. THE AES CORPORATION SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PARENT STATEMENTS OF OPERATIONS For the Years Ended December 31, 2017 2016 2015 (in millions) Revenue from subsidiaries and affiliates $ 28 $ 14 $ 24 Equity in earnings of subsidiaries and affiliates 630 (615 ) 859 Interest income 49 19 24 General and administrative expenses (158 ) (144 ) (154 ) Other income 5 7 24 Other expense (554 ) (65 ) (6 ) Loss on extinguishment of debt (92 ) (14 ) (105 ) Interest expense (317 ) (344 ) (364 ) Income (loss) before income taxes (409 ) (1,142 ) 302 Income tax benefit (expense) (752 ) 12 4 Net income (loss) $ (1,161 ) $ (1,130 ) $ 306 See Notes to Schedule I. THE AES CORPORATION SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PARENT STATEMENTS OF COMPREHENSIVE LOSS YEARS ENDED DECEMBER 31, 2017 , 2016 , AND 2015 2017 2016 2015 (in millions) NET INCOME (LOSS) $ (1,161 ) $ (1,130 ) $ 306 Foreign currency translation activity: Foreign currency translation adjustments, net of income tax benefit (expense) of $11, $1 and $1, respectively 18 117 (674 ) Reclassification to earnings, net of $0 income tax for all periods 643 992 — Total foreign currency translation adjustments, net of tax 661 1,109 (674 ) Derivative activity: Change in derivative fair value, net of income tax benefit (expense) of $13, $(5) and $4, respectively (14 ) 2 (5 ) Reclassification to earnings, net of income tax benefit (expense) of $1, $1 and $(12), respectively 37 28 48 Total change in fair value of derivatives, net of tax 23 30 43 Pension activity: Prior service cost for the period, net of income tax expense of $1, $5 and $0, respectively 1 9 1 Change in pension adjustments due to net actuarial gain (loss) for the period, net of income tax benefit (expense) of $6, $10 and $(7), respectively (20 ) (22 ) 18 Reclassification of earnings due to amortization of net actuarial loss, net of income tax benefit (expense) of $(126), $2 and $(2), respectively 248 1 2 Total change in unfunded pension obligation 229 (12 ) 21 OTHER COMPREHENSIVE INCOME (LOSS) 913 1,127 (610 ) COMPREHENSIVE LOSS $ (248 ) $ (3 ) $ (304 ) See Notes to Schedule I. THE AES CORPORATION SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PARENT STATEMENTS OF CASH FLOWS For the Years Ended December 31, 2017 2016 2015 (in millions) Net cash provided by operating activities $ 148 $ 818 $ 475 Investing Activities: Investment in and net advances to subsidiaries (339 ) (650 ) (221 ) Return of capital 243 247 501 Decrease in restricted cash 3 29 49 Additions to property, plant and equipment (13 ) (12 ) (11 ) Net cash provided by (used in) investing activities (106 ) (386 ) 318 Financing Activities: Borrowings under the revolver, net 207 — — Borrowings of notes payable and other coupon bearing securities 1,025 500 575 Repayments of notes payable and other coupon bearing securities (1,353 ) (808 ) (915 ) Loans from subsidiaries 309 183 — Purchase of treasury stock — (79 ) (482 ) Proceeds from issuance of common stock 1 1 4 Common stock dividends paid (317 ) (290 ) (276 ) Payments for deferred financing costs (12 ) (12 ) (6 ) Distributions to noncontrolling interests — (2 ) — Other financing (7 ) (3 ) (18 ) Net cash used in financing activities (147 ) (510 ) (1,118 ) Effect of exchange rate changes on cash 6 1 — Decrease in cash and cash equivalents (99 ) (77 ) (325 ) Cash and cash equivalents, beginning 109 186 511 Cash and cash equivalents, ending $ 10 $ 109 $ 186 Supplemental Disclosures: Cash payments for interest, net of amounts capitalized $ 282 $ 296 $ 314 Cash payments for income taxes, net of refunds $ 2 $ 6 $ — See Notes to Schedule I SCHEDULE I NOTES TO SCHEDULE I 1. Application of Significant Accounting Principles The Schedule I Condensed Financial Information of the Parent includes the accounts of The AES Corporation (the “Parent Company”) and certain holding companies. ACCOUNTING FOR SUBSIDIARIES AND AFFILIATES — The Parent Company has accounted for the earnings of its subsidiaries on the equity method in the financial information. INCOME TAXES — Positions taken on the Parent Company's income tax return which satisfy a more-likely-than-not threshold will be recognized in the financial statements. The income tax expense or benefit computed for the Parent Company reflects the tax assets and liabilities on a stand-alone basis and the effect of filing a consolidated U.S. income tax return with certain other affiliated companies as well as effects of U.S. tax law reform enacted in 2017. ACCOUNTS AND NOTES RECEIVABLE FROM SUBSIDIARIES — Amounts have been shown in current or long-term assets based on terms in agreements with subsidiaries, but payment is dependent upon meeting conditions precedent in the subsidiary loan agreements. Senior and Secured Notes and Loans Payable ($ in millions) December 31, Interest Rate Maturity 2017 2016 Senior Unsecured Note LIBOR + 3.00% 2019 $ — $ 240 Senior Unsecured Note 8.00% 2020 228 469 Senior Unsecured Note 7.38% 2021 690 966 Drawings on secured credit facility LIBOR + 2.00% 2021 207 — Senior Secured Term Loan LIBOR + 2.00% 2022 521 — Senior Unsecured Note 4.88% 2023 713 713 Senior Unsecured Note 5.50% 2024 738 738 Senior Unsecured Note 5.50% 2025 573 573 Senior Unsecured Note 6.00% 2026 500 500 Senior Unsecured Note 5.13% 2027 500 — Unamortized (discounts)/premiums & debt issuance (costs) (40 ) (45 ) Subtotal $ 4,630 $ 4,154 Less: Current maturities (5 ) — Total $ 4,625 $ 4,154 Junior Subordinated Notes Payable ($ in millions) December 31, Interest Rate Maturity 2017 2016 Term Convertible Trust Securities 6.75% 2029 $ — $ 517 FUTURE MATURITIES OF RECOURSE DEBT — As of December 31, 2017 scheduled maturities are presented in the following table (in millions): December 31, Annual Maturities 2018 $ 5 2019 5 2020 234 2021 902 2022 500 Thereafter 3,024 Unamortized (discount)/premium & debt issuance (costs) (40 ) Total debt $ 4,630 Dividends from Subsidiaries and Affiliates Cash dividends received from consolidated subsidiaries were $1.2 billion , $1 billion , and $748 million for the years ended December 31, 2017 , 2016 , and 2015 , respectively. There were no cash dividends received from affiliates accounted for by the equity method for the years ended December 31, 2017 , 2016 , and 2015 . Guarantees and Letters of Credit GUARANTEES — In connection with certain of its project financing, acquisition, and power purchase agreements, the Parent Company has expressly undertaken limited obligations and commitments, most of which will only be effective or will be terminated upon the occurrence of future events. These obligations and commitments, excluding those collateralized by letter of credit and other obligations discussed below, were limited as of December 31, 2017 , by the terms of the agreements, to an aggregate of approximately $842 million representing 22 agreements with individual exposures ranging from $1 million to $272 million . These amounts exclude normal and customary representations and warranties in agreements for the sale of assets (including ownership in associated legal entities) where the associated risk is considered to be nominal. LETTERS OF CREDIT — At December 31, 2017 , the Parent Company had $36 million in letters of credit outstanding under the senior secured credit facility, representing 21 agreements with individual exposures up to $13 million , and $52 million in letters of credit outstanding under the senior unsecured credit facility, representing 4 agreements with individual exposures ranging from $2 million to $26 million . During 2017 , the Parent Company paid letter of credit fees ranging from 0.25% to 2.25% per annum on the outstanding amounts.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS	SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS (in millions) Balance at Beginning of the Period Charged to Cost and Expense Amounts Written off Translation Adjustment Balance at End of the Period Allowance for accounts receivables (current and noncurrent)

General and Summary of Signif41

General and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
PRINCIPLES OF CONSOLIDATION	PRINCIPLES OF CONSOLIDATION — The consolidated financial statements of the Company include the accounts of The AES Corporation and its controlled subsidiaries. Furthermore, VIEs in which the Company has an ownership interest and is the primary beneficiary, thus controlling the VIE, have been consolidated. Intercompany transactions and balances are eliminated in consolidation. Investments in entities where the Company has the ability to exercise significant influence, but not control, are accounted for using the equity method of accounting.
USE OF ESTIMATES	USE OF ESTIMATES — US GAAP requires the Company to make estimates and assumptions that affect the asset and liability balances reported as of the date of the consolidated financial statements, as well as the revenues and expenses recognized during the reporting period. Actual results could differ from those estimates. Items subject to such estimates and assumptions include: the carrying amount and estimated useful lives of long-lived assets; asset retirement obligations; impairment of goodwill, long-lived assets and equity method investments; valuation allowances for receivables and deferred tax assets; the recoverability of regulatory assets; regulatory liabilities; the fair value of financial instruments; the fair value of assets and liabilities acquired in a business combination; the measurement of equity method investments or noncontrolling interest using the HLBV method for certain renewable generation partnerships; the determination of whether a sale of noncontrolling interests is considered to be a sale of in-substance real estate (as opposed to an equity transaction); pension liabilities; environmental liabilities; the impact of U.S. tax reform; and potential litigation claims and settlements.
DISCONTINUED OPERATIONS AND RECLASSIFICATIONS	DISCONTINUED OPERATIONS — Discontinued operations reporting occurs only when the disposal of a business or a group of businesses represents a strategic shift that has (or will have) a major effect on the Company's operations and financial results. The Company reports financial results for discontinued operations separately from continuing operations to distinguish the financial impact of disposal transactions from ongoing operations. Prior period amounts in the statement of operations and balance sheet are retrospectively revised to reflect the businesses determined to be discontinued operations. The cash flows of businesses that are determined to be discontinued operations are included within the relevant categories within operating, investing and financing activities on the face of the Statements of Cash Flows. Transactions between the businesses determined to be discontinued operations and businesses that are expected to continue to exist after the disposal are not eliminated to appropriately reflect the continuing operations and balances held for sale. The results of discontinued operations include any gain or loss recognized on closing or adjustment of the carrying amount to fair value less cost to sell, including gains or losses associated with noncontrolling interests upon completion of the disposal transaction. See Note 21 — Discontinued Operations for further information.
FAIR VALUE	FAIR VALUE — Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly, hypothetical transaction between market participants at the measurement date, or exit price. The Company applies the fair value measurement accounting guidance to financial assets and liabilities in determining the fair value of investments in marketable debt and equity securities, included in the Consolidated Balance Sheet line items Short-term investments and Other assets (noncurrent) ; derivative assets, included in Other current assets and Other assets (noncurrent) ; and, derivative liabilities, included in Accrued and other liabilities (current) and Other long-term liabilities . The Company applies the fair value measurement guidance to nonfinancial assets and liabilities upon the acquisition of a business or in conjunction with the measurement of an asset retirement obligation or a potential impairment loss on an asset group or goodwill. When determining the fair value measurements for assets and liabilities required to be reflected at their fair values, the Company considers the principal or most advantageous market in which it would transact and considers assumptions that market participants would use when pricing the assets or liabilities, such as inherent risk, transfer restrictions and risk of nonperformance. The Company is prohibited from including transaction costs and any adjustments for blockage factors in determining fair value. In determining fair value measurements, the Company maximizes the use of observable inputs and minimizes the use of unobservable inputs. Assets and liabilities are categorized within a fair value hierarchy based upon the lowest level of input that is significant to the fair value measurement: • Level 1: Quoted prices in active markets for identical assets or liabilities • Level 2: Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices in active markets for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; or • Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair values of the assets or liabilities Any transfers between all levels within the fair value hierarchy levels are recognized at the end of the reporting period.
CASH AND CASH EQUIVALENTS	CASH AND CASH EQUIVALENTS — The Company considers unrestricted cash on hand, cash balances not restricted as to withdrawal or usage, deposits in banks, certificates of deposit and short-term marketable securities with original maturities of three months or less to be cash and cash equivalents.
RESTRICTED CASH AND DEBT SERVICE RESERVES	RESTRICTED CASH AND DEBT SERVICE RESERVES — Cash balances restricted as to withdrawal or usage, primarily via contract, are considered restricted cash.
INVESTMENTS IN MARKETABLE SECURITIES	INVESTMENTS IN MARKETABLE SECURITIES — The Company's marketable investments are primarily unsecured debentures, certificates of deposit, government debt securities and money market funds. Short-term investments consist of marketable equity securities and debt securities with original maturities in excess of three months with remaining maturities of less than one year. Marketable debt securities where the Company has both the positive intent and ability to hold to maturity are classified as held-to-maturity and are carried at amortized cost. Remaining marketable securities are classified as available-for-sale or trading and are carried at fair value. Available-for-sale and trading investment's unrealized gains or losses are reflected in AOCL, a separate component of equity, and the Consolidated Statements of Operations, respectively .. Interest and dividends on investments are reported in interest income and other income , respectively. Gains and losses on sales of investments are determined using the specific identification method.
ACCOUNTS AND NOTES RECEIVABLE AND ALLOWANCE FOR DOUBTFUL ACCOUNTS	ACCOUNTS AND NOTES RECEIVABLE AND ALLOWANCE FOR DOUBTFUL ACCOUNTS — Accounts and notes receivable are carried at amortized cost. The Company periodically assesses the collectability of accounts receivable, considering factors such as historical collection experience, the age of accounts receivable and other currently available evidence supporting collectability, and records an allowance for doubtful accounts for the estimated uncollectible amount as appropriate. Certain of our businesses charge interest on accounts receivable. Interest income is recognized on an accrual basis. When collection of such interest is not reasonably assured, interest income is recognized as cash is received. Individual accounts and notes receivable are written off when they are no longer deemed collectible.
INVENTORY	INVENTORY — Inventory primarily consists of fuel and other raw materials used to generate power, and operational spare parts and supplies used to maintain power generation and distribution facilities. Inventory is carried at lower of cost or net realizable value. Cost is the sum of the purchase price and expenditures incurred to bring the inventory to its existing location. Inventory is primarily valued using the average cost method. Generally, if it is expected fuel inventory will not be recovered through revenue earned from power generation, an impairment is recognized to reflect the fuel at market value.
LONG-LIVED ASSETS	LONG-LIVED ASSETS — Long-lived assets include property, plant and equipment, assets under capital leases and intangible assets subject to amortization (i.e., finite-lived intangible assets). Property, plant and equipment — Property, plant and equipment are stated at cost, net of accumulated depreciation. The cost of renewals and improvements that extend the useful life of property, plant and equipment are capitalized. Construction progress payments, engineering costs, insurance costs, salaries, interest and other costs directly relating to construction in progress are capitalized during the construction period, provided the completion of the construction project is deemed probable, or expensed at the time construction completion is determined to no longer be probable. The continued capitalization of such costs is subject to risks related to successful completion, including those related to government approvals, site identification, financing, construction permitting and contract compliance. Construction-in-progress balances are transferred to electric generation and distribution assets when an asset group is ready for its intended use. Government subsidies, liquidated damages recovered for construction delays, and income tax credits are recorded as a reduction to property, plant and equipment and reflected in cash flows from investing activities. Maintenance and repairs are charged to expense as incurred. Depreciation, after consideration of salvage value and asset retirement obligations, is computed using the straight-line method over the estimated useful lives of the assets, which are determined on a composite or component basis. Capital spare parts, including rotable spare parts, are included in electric generation and distribution assets. If the spare part is considered a component, it is depreciated over its useful life after the part is placed in service. If the spare part is deemed part of a composite asset, the part is depreciated over the composite useful life even when being held as a spare part. The Company's Brazilian subsidiaries operate under concession contracts. Certain estimates are utilized to determine depreciation expense for the Brazilian subsidiaries, including the useful lives of the property, plant and equipment and the amounts to be recovered at the end of the concession contract. The amounts to be recovered under these concession contracts are based on estimates that are inherently uncertain and actual amounts recovered may differ from those estimates.
INTANGIBLE ASSETS SUBJECT TO AMORTIZATION	Intangible Assets Subject to Amortization — Finite-lived intangible assets are amortized over their useful lives which range from 3 – 50 years. The Company accounts for purchased emission allowances as intangible assets and records an expense when they are utilized or sold. Granted emission allowances are valued at zero.
IMPAIRMENT OF LONG-LIVED ASSETS	Impairment of Long-lived Assets — When circumstances indicate the carrying amount of long-lived assets in a held-for-use asset group may not be recoverable, the Company evaluates the assets for potential impairment using internal projections of undiscounted cash flows resulting from the use and eventual disposal of the assets. Events or changes in circumstances that may necessitate a recoverability evaluation include, but are not limited to, adverse changes in the regulatory environment, unfavorable changes in power prices or fuel costs, increased competition due to additional capacity in the grid, technological advancements, declining trends in demand, or an expectation it is more likely than not that the asset will be disposed of before the end of its previously estimated useful life. If the carrying amount of the assets exceeds the undiscounted cash flows, an impairment expense is recognized for the amount by which the carrying amount of the asset group exceeds its fair value (subject to the carrying amount not being reduced below fair value for any individual long-lived asset that is determinable without undue cost and effort). An impairment expense for certain assets may be reduced by the establishment of a regulatory asset if recovery through approved rates is probable.
DEFERRED FINANCING COSTS	DEBT ISSUANCE COSTS — Costs incurred in connection with the issuance of long-term debt are deferred and presented as a direct reduction from the face amount of that debt and amortized over the related financing period using the effective interest method. Debt issuance costs related to a line-of-credit or revolving credit facility are deferred and presented as an asset and amortized over the related financing period. Make-whole payments in connection with early debt retirements are classified as cash flows used in financing activities.
EQUITY METHOD INVESTMENTS	.
GOODWILL AND INDEFINITE-LIVED INTANGIBLE ASSETS	GOODWILL AND INDEFINITE-LIVED INTANGIBLE ASSETS — The Company evaluates goodwill and indefinite-lived intangible assets for impairment on an annual basis and whenever events or changes in circumstances necessitate an evaluation for impairment. The Company's annual impairment testing date is October first. Goodwill — Goodwill represents the excess of the purchase price of the business acquisition over the fair value of identifiable net assets acquired. Goodwill resulting from an acquisition is assigned to the reporting units that are expected to benefit from the synergies of the acquisition. Generally, each AES business with a goodwill balance constitutes a reporting unit as they are not similar to other businesses in a segment nor are they reported to segment management together with other businesses. Goodwill is evaluated for impairment either under the qualitative assessment option or the two-step quantitative test. If goodwill is determined to be impaired, the fair value of individual assets and liabilities is determined to compute the implied fair value of goodwill. If the carrying amount of goodwill exceeds its implied fair value, the excess is recognized as an impairment loss up to the carrying amount of the goodwill. Indefinite-Lived Intangible Assets — The Company's indefinite-lived intangible assets primarily include land-use rights and water rights. Indefinite-lived Intangible Assets are evaluated for impairment either under the qualitative assessment option or the two-step quantitative test. If the carrying amount of an intangible asset being tested for impairment exceeds its fair value, the excess is recognized as impairment expense.
ACCOUNTS PAYABLE AND OTHER ACCRUED LIABILITIES	ACCOUNTS PAYABLE AND OTHER ACCRUED LIABILITIES — Accounts payable consists of amounts due to trade creditors related to the Company's core business operations. These payables include amounts owed to vendors and suppliers for items such as energy purchased for resale, fuel, maintenance, inventory and other raw materials. Other accrued liabilities include items such as income taxes, regulatory liabilities, legal contingencies and employee-related costs, including payroll, benefits and related taxes.
REGULATORY ASSETS AND LIABILITIES	REGULATORY ASSETS AND LIABILITIES — The Company recognizes assets and liabilities that result from regulated ratemaking processes. Regulatory assets generally represent incurred costs which have been deferred due to the probable future recovery via customer rates. Generally, returns earned on regulatory assets are reflected in the Consolidated Statement of Operations within Interest Income . Regulatory liabilities generally represent obligations to refund customers. Management continually assesses whether regulatory assets are probable of future recovery and regulatory liabilities are probable of future payment by considering factors such as applicable regulatory changes, recent rate orders applicable to other regulated entities, and the status of any pending or potential deregulation legislation. If future recovery of costs previously deferred ceases to be probable, the related regulatory assets are written off and recognized in income from continuing operations.
PENSION AND OTHER POSTRETIREMENT PLANS	PENSION AND OTHER POSTRETIREMENT PLANS — The Company recognizes in its Consolidated Balance Sheets an asset or liability reflecting the funded status of pension and other postretirement plans with current-year changes in actuarial gains or losses recognized in AOCL, except for those plans at certain of the Company's regulated utilities that can recover portions of their pension and postretirement obligations through future rates. All plan assets are recorded at fair value. AES follows the measurement date provisions of the accounting guidance, which require a year-end measurement date of plan assets and obligations for all defined benefit plans.
INCOME TAXES	INCOME TAXES — Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of the existing assets and liabilities, and their respective income tax bases. The Company establishes a valuation allowance when it is more likely than not that all or a portion of a deferred tax asset will not be realized. The Company's tax positions are evaluated under a more likely than not recognition threshold and measurement analysis before they are recognized for financial statement reporting. Uncertain tax positions have been classified as noncurrent income tax liabilities unless expected to be paid within one year. The Company's policy for interest and penalties related to income tax exposures is to recognize interest and penalties as a component of the provision for income taxes in the Consolidated Statements of Operations. The Company's policy for interest and penalties related to income tax exposures is to recognize interest and penalties as a component of the provision for income taxes in the Consolidated Statements of Operations.
ASSET RETIREMENT OBLIGATIONS	ASSET RETIREMENT OBLIGATIONS — The Company records the fair value of a liability for a legal obligation to retire an asset in the period in which the obligation is incurred. When a new liability is recognized, the Company capitalizes the costs of the liability by increasing the carrying amount of the related long-lived asset. The liability is accreted to its present value each period and the capitalized cost is depreciated over the useful life of the related asset. Upon settlement of the obligation, the Company eliminates the liability and, based on the actual cost to retire, may incur a gain or loss.
NONCONTROLLING INTERESTS	.
FOREIGN CURRENCY TRANSLATION	FOREIGN CURRENCY TRANSLATION — A business's functional currency is the currency of the primary economic environment in which the business operates and is generally the currency in which the business generates and expends cash. Subsidiaries and affiliates whose functional currency is a currency other than the U.S. dollar translate their assets and liabilities into U.S. dollars at the current exchange rates in effect at the end of the fiscal period. Adjustments arising from the translation of the balance sheet of such subsidiaries are included in AOCL. The revenue and expense accounts of such subsidiaries and affiliates are translated into U.S. dollars at the average exchange rates for the period. Gains and losses on intercompany foreign currency transactions that are long-term in nature and which the Company does not intend to settle in the foreseeable future, are also recognized in AOCL. Gains and losses that arise from exchange rate fluctuations on transactions denominated in a currency other than the functional currency are included in determining net income. Accumulated foreign currency translation adjustments are reclassified from AOCL to net income only when realized upon sale or upon complete or substantially complete liquidation of the investment in a foreign entity. The accumulated adjustments are included in carrying amounts in impairment assessments where the Company has committed to a plan that will cause the accumulated adjustments to be reclassified to earnings
REVENUE RECOGNITION	REVENUE RECOGNITION — Revenue from utilities is classified as regulated in the Consolidated Statements of Operations. Revenue from the sale of energy is recognized in the period during which the sale occurs. The calculation of revenue earned but not yet billed is based on the number of days not billed in the month, the estimated amount of energy delivered during those days and the estimated average price per customer class for that month. Differences between actual and estimated unbilled revenue are usually immaterial. The Company has businesses where it sells and purchases power to and from ISOs and RTOs. In those instances, the Company accounts for these transactions on a net hourly basis because the transactions are settled on a net hourly basis. Revenue from generation businesses is classified as non-regulated in the Consolidated Statements of Operations. Revenue is recognized based upon output delivered and capacity provided, at rates as specified under contract terms or prevailing market rates. Certain of the Company's PPAs meet the definition of an operating lease or contain similar arrangements. Typically, minimum lease payments from such PPAs are recognized as revenue on a straight-line basis over the lease term whereas contingent rentals are recognized when earned. Revenue is recorded net of any taxes assessed on and collected from customers, which are remitted to the governmental authorities.
SHARE-BASED COMPENSATION	SHARE-BASED COMPENSATION — The Company grants share-based compensation in the form of stock options, restricted stock units, performance stock units, and performance cash units. The expense is based on the grant-date fair value of the equity or liability instrument issued and is recognized on a straight-line basis over the requisite service period, net of estimated forfeitures. The Company uses a Black-Scholes option pricing model to estimate the fair value of stock options granted to its employees.
GENERAL AND ADMINISTRATIVE EXPENSES	GENERAL AND ADMINISTRATIVE EXPENSES — General and administrative expenses include corporate and other expenses related to corporate staff functions and initiatives, primarily executive management, finance, legal, human resources and information systems, which are not directly allocable to our business segments. Additionally, all costs associated with corporate business development efforts are classified as general and administrative expenses.
DERIVATIVES AND HEDGING ACTIVITIES	DERIVATIVES AND HEDGING ACTIVITIES — Under the accounting standards for derivatives and hedging, the Company recognizes all contracts that meet the definition of a derivative, except those designated as normal purchase or normal sale at inception, as either assets or liabilities in the Consolidated Balance Sheets and measures those instruments at fair value. See the Company's fair value policy and Note 4— Fair Value and Fair value in this section for additional discussion regarding the determination of fair value. PPAs and fuel supply agreements are evaluated to assess if they contain either a derivative or an embedded derivative requiring separate valuation and accounting. Generally, these agreements do not meet the definition of a derivative, often due to the inability to be net settled. On a quarterly basis, we evaluate the markets for commodities to be delivered under these agreements to determine if facts and circumstances have changed such that the agreements could be net settled and meet the definition of a derivative. The Company typically designates its derivative instruments as cash flow hedges if they meet the criteria specified in ASC 815, Derivatives and Hedging . The Company enters into interest rate swap agreements in order to hedge the variability of expected future cash interest payments. Foreign currency contracts are used to reduce risks arising from the change in fair value of certain foreign currency denominated assets and liabilities. The objective of these practices is to minimize the impact of foreign currency fluctuations on operating results. The Company also enters into commodity contracts to economically hedge price variability inherent in electricity sales arrangements. The objectives of the commodity contracts are to minimize the impact of variability in spot electricity prices and stabilize estimated revenue streams. The Company does not use derivative instruments for speculative purposes. For our hedges, changes in fair value that are considered highly effective are deferred in AOCL and are recognized into earnings as the hedged transactions affect earnings. Any ineffectiveness is recognized in earnings immediately. If a derivative is no longer highly effective, hedge accounting will be discontinued prospectively. For cash flow hedges of forecasted transactions, AES estimates the future cash flows of the forecasted transactions and evaluates the probability of the occurrence and timing of such transactions. Changes in the fair value of derivatives not designated and qualifying as cash flow hedges are immediately recognized in earnings. Regardless of when gains or losses on derivatives are recognized in earnings, they are generally classified as interest expense for interest rate and cross-currency derivatives, foreign currency transaction gains or losses for foreign currency derivatives, and non-regulated revenue or non-regulated cost of sales for commodity and other derivatives. Cash flows arising from derivatives are included in the Consolidated Statements of Cash Flows as an operating activity given the nature of the underlying risk being economically hedged and the lack of significant financing elements, except that cash flows on designated and qualifying hedges of variable-rate interest during construction are classified as an investing activity.
DERIVATIVES OFFSETTING FAIR VALUE AMOUNTS	The Company has elected not to offset net derivative positions in the financial statements.
NEW ACCOUNTING PRONOUNCEMENTS ADOPTED	NEW ACCOUNTING PRONOUNCEMENTS — The following table provides a brief description of recent accounting pronouncements that had and/or could have a material impact on the Company’s consolidated financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or are expected to have no material impact on the Company’s consolidated financial statements. New Accounting Standards Adopted ASU Number and Name Description Date of Adoption Effect on the financial statements upon adoption 2016-09, Compensation — Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting The standard simplifies the following aspects of accounting for share-based payments awards: accounting for income taxes, classification of excess tax benefits on the statement of cash flows, forfeitures, statutory tax withholding requirements, classification of awards as either equity or liabilities and classification of employee taxes paid on statement of cash flows when an employer withholds shares for tax-withholding purposes. January 1, 2017 The recognition of excess tax benefits in the provision for income taxes in the period when the awards vest or are settled, rather than in paid-in-capital in the period when the excess tax benefits are realized, resulted in a decrease of $31 million to deferred tax liabilities, offset by an increase to retained earnings. New Accounting Standards Issued But Not Yet Effective ASU Number and Name Description Date of Adoption Effect on the financial statements upon adoption 2018-02, Income Statement — Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from AOCI This amendment allows a reclassification of the stranded tax effects resulting from the implementation of the Tax Cuts and Jobs Act from AOCI to retained earnings. Because this amendment only relates to the reclassification of the income tax effects of the Tax Cuts and Jobs Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-12, Derivatives and Hedging (Topic 815): Targeted improvements to Accounting for Hedging Activities The standard updates the hedge accounting model to expand the ability to hedge nonfinancial and financial risk components, reduce complexity, and ease certain documentation and assessment requirements. When facts and circumstances are the same as at the previous quantitative test, a subsequent quantitative effectiveness test is not required. The standard also eliminates the requirement to separately measure and report hedge ineffectiveness. For cash flow hedges, this means that the entire change in the fair value of a hedging instrument will be recorded in other comprehensive income and amounts deferred will be reclassified to earnings in the same income statement line as the hedged item. Transition method: modified retrospective with the cumulative effect adjustment recorded to the opening balance of retained earnings as of the initial application date. Prospective for presentation and disclosures. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-11, Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815): Accounting for Certain Financial Instruments and Certain Mandatorily Redeemable Noncontrolling Interests Part 1 of this standard changes the classification of certain equity-linked financial instruments when assessing whether the instrument is indexed to an entity’s own stock. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-08, Receivables — Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities This standard shortens the period of amortization for the premium on certain callable debt securities to the earliest call date. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-05, Other Income — Gains and Losses from the Derecognition of Nonfinancial Assets (Topic 610-20) This standard clarifies the scope and application of ASC 610-20 on the sale, transfer, and derecognition of nonfinancial assets and in substance nonfinancial assets to non-customers, including partial sales. It also clarifies that the derecognition of businesses is under scope of ASC 810. The standard must be adopted concurrently with ASC 606, however an entity will not have to apply the same transition method as ASC 606. January 1, 2018. Early adoption is permitted only as of January 1, 2017. The Company does not expect any impact on its consolidated financial statements upon adoption of the standard, will adopt the standard on January 1, 2018, and plans to use the modified retrospective approach. 2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment This standard simplifies the accounting for goodwill impairment by removing the requirement to calculate the implied fair value. Instead, it requires that an entity records an impairment charge based on the excess of a reporting unit's carrying amount over its fair value. January 1, 2020. Early adoption is permitted as of January 1, 2017. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business The standard requires an entity to first evaluate whether substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets, and if that threshold is met, the set is not a business. As a second step, to be considered a business at least one substantive process should exist. The revised definition of a business will reduce the number of transactions that are accounted for as business combinations. Transition Method: prospective. January 1, 2018. Early adoption is permitted. This revised definition will reduce the number of transactions that are accounted for as a business, therefore, acquisitions and disposition would fall under a different accounting model. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force) This standard requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. January 1, 2018. Early adoption is permitted. The Company has performed a preliminary evaluation and expects an increase in cash provided by operating activities of approximately $5 million for 2017 and 2016 and a decrease of $5 million in 2015. Net cash used in investing activities are expected to decrease by approximately $150 million and $230 million for 2017 and 2015, respectively, with an increase of $10 million expected for 2016. 2016-13, Financial Instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments The standard updates the impairment model for financial assets measured at amortized cost. For trade and other receivables, held-to-maturity debt securities, loans and other instruments, entities will be required to use a new forward-looking "expected loss" model that generally will result in the earlier recognition of allowance for losses. For available-for-sale debt securities with unrealized losses, entities will measure credit losses as it is done today, except that the losses will be recognized as an allowance rather than a reduction in the amortized cost of the securities. Transition method: various. January 1, 2020. Early adoption is permitted only as of January 1, 2019. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2016-02, 2018-01, Leases (Topic 842) See discussion of the ASU below. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements and intends to adopt the standard as of January 1, 2019. 2014-09, 2015-14, 2016-08, 2016-10, 2016-12, 2016-20, 2017-10, 2017-13, Revenue from Contracts with Customers (Topic 606) See discussion of the ASU below. January 1, 2018. Early adoption is permitted only as of January 1, 2017. The Company will adopt the standard on January 1, 2018; see below for the evaluation of the impact of its adoption on the consolidated financial statements.
ACCOUNTING PRONOUNCEMENTS ISSUED BUT NOT YET EFFECTIVE	New Accounting Standards Issued But Not Yet Effective ASU Number and Name Description Date of Adoption Effect on the financial statements upon adoption 2018-02, Income Statement — Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from AOCI This amendment allows a reclassification of the stranded tax effects resulting from the implementation of the Tax Cuts and Jobs Act from AOCI to retained earnings. Because this amendment only relates to the reclassification of the income tax effects of the Tax Cuts and Jobs Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-12, Derivatives and Hedging (Topic 815): Targeted improvements to Accounting for Hedging Activities The standard updates the hedge accounting model to expand the ability to hedge nonfinancial and financial risk components, reduce complexity, and ease certain documentation and assessment requirements. When facts and circumstances are the same as at the previous quantitative test, a subsequent quantitative effectiveness test is not required. The standard also eliminates the requirement to separately measure and report hedge ineffectiveness. For cash flow hedges, this means that the entire change in the fair value of a hedging instrument will be recorded in other comprehensive income and amounts deferred will be reclassified to earnings in the same income statement line as the hedged item. Transition method: modified retrospective with the cumulative effect adjustment recorded to the opening balance of retained earnings as of the initial application date. Prospective for presentation and disclosures. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-11, Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815): Accounting for Certain Financial Instruments and Certain Mandatorily Redeemable Noncontrolling Interests Part 1 of this standard changes the classification of certain equity-linked financial instruments when assessing whether the instrument is indexed to an entity’s own stock. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-08, Receivables — Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities This standard shortens the period of amortization for the premium on certain callable debt securities to the earliest call date. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-05, Other Income — Gains and Losses from the Derecognition of Nonfinancial Assets (Topic 610-20) This standard clarifies the scope and application of ASC 610-20 on the sale, transfer, and derecognition of nonfinancial assets and in substance nonfinancial assets to non-customers, including partial sales. It also clarifies that the derecognition of businesses is under scope of ASC 810. The standard must be adopted concurrently with ASC 606, however an entity will not have to apply the same transition method as ASC 606. January 1, 2018. Early adoption is permitted only as of January 1, 2017. The Company does not expect any impact on its consolidated financial statements upon adoption of the standard, will adopt the standard on January 1, 2018, and plans to use the modified retrospective approach. 2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment This standard simplifies the accounting for goodwill impairment by removing the requirement to calculate the implied fair value. Instead, it requires that an entity records an impairment charge based on the excess of a reporting unit's carrying amount over its fair value. January 1, 2020. Early adoption is permitted as of January 1, 2017. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business The standard requires an entity to first evaluate whether substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets, and if that threshold is met, the set is not a business. As a second step, to be considered a business at least one substantive process should exist. The revised definition of a business will reduce the number of transactions that are accounted for as business combinations. Transition Method: prospective. January 1, 2018. Early adoption is permitted. This revised definition will reduce the number of transactions that are accounted for as a business, therefore, acquisitions and disposition would fall under a different accounting model. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force) This standard requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. January 1, 2018. Early adoption is permitted. The Company has performed a preliminary evaluation and expects an increase in cash provided by operating activities of approximately $5 million for 2017 and 2016 and a decrease of $5 million in 2015. Net cash used in investing activities are expected to decrease by approximately $150 million and $230 million for 2017 and 2015, respectively, with an increase of $10 million expected for 2016. 2016-13, Financial Instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments The standard updates the impairment model for financial assets measured at amortized cost. For trade and other receivables, held-to-maturity debt securities, loans and other instruments, entities will be required to use a new forward-looking "expected loss" model that generally will result in the earlier recognition of allowance for losses. For available-for-sale debt securities with unrealized losses, entities will measure credit losses as it is done today, except that the losses will be recognized as an allowance rather than a reduction in the amortized cost of the securities. Transition method: various. January 1, 2020. Early adoption is permitted only as of January 1, 2019. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2016-02, 2018-01, Leases (Topic 842) See discussion of the ASU below. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements and intends to adopt the standard as of January 1, 2019. 2014-09, 2015-14, 2016-08, 2016-10, 2016-12, 2016-20, 2017-10, 2017-13, Revenue from Contracts with Customers (Topic 606) See discussion of the ASU below. January 1, 2018. Early adoption is permitted only as of January 1, 2017. The Company will adopt the standard on January 1, 2018; see below for the evaluation of the impact of its adoption on the consolidated financial statements.
SEGMENTS AND GEOGRAPHIC INFORMATION	The segment reporting structure uses the Company's organizational structure as its foundation to reflect how the Company manages the businesses internally and is organized by geographic regions which provides a socio-political-economic understanding of our business. During the third quarter of 2017, the Europe and Asia SBUs were merged in order to leverage scale and are now reported as part of the Eurasia SBU. The management reporting structure is organized by five SBUs led by our President and Chief Executive Officer: US, Andes, Brazil, MCAC and Eurasia SBUs. The Company determined that it has five operating and five reportable segments corresponding to its SBUs. All prior period results have been retrospectively revised to reflect the new segment reporting structure. In February 2018, we announced a reorganization as a part of our ongoing strategy to simplify our portfolio, optimize our cost structure, and reduce our carbon intensity. The Company is currently evaluating the impact this reorganization will have on our segment reporting structure. Corporate and Other — Corporate overhead costs which are not directly associated with the operations of our five reportable segments are included in "Corporate and Other." Also included are certain intercompany charges such as self-insurance premiums which are fully eliminated in consolidation. The Company uses Adjusted PTC as its primary segment performance measure. Adjusted PTC, a non-GAAP measure, is defined by the Company as pre-tax income from continuing operations attributable to The AES Corporation excluding gains or losses of the consolidated entity due to (a) unrealized gains or losses related to derivative transactions; (b) unrealized foreign currency gains or losses; (c) gains, losses and associated benefits and costs due to dispositions and acquisitions of business interests, including early plant closures; (d) losses due to impairments; (e) gains, losses and costs due to the early retirement of debt; and (f) costs directly associated with a major restructuring program, including, but not limited to, workforce reduction efforts, relocations, and office consolidation . Adjusted PTC also includes net equity in earnings of affiliates on an after-tax basis adjusted for the same gains or losses excluded from consolidated entities. The Company has concluded Adjusted PTC better reflects the underlying business performance of the Company and is the most relevant measure considered in the Company's internal evaluation of the financial performance of its segments. Additionally, given its large number of businesses and complexity, the Company concluded that Adjusted PTC is a more transparent measure that better assists investors in determining which businesses have the greatest impact on the Company's results. Revenue and Adjusted PTC are presented before inter-segment eliminations, which includes the effect of intercompany transactions with other segments except for interest, charges for certain management fees, and the write-off of intercompany balances, as applicable. All intra-segment activity has been eliminated within the segment. Inter-segment activity has been eliminated within the total consolidated results.
Earnings Per Share, Policy [Policy Text Block]	Basic and diluted earnings per share are based on the weighted-average number of shares of common stock and potential common stock outstanding during the period. Potential common stock, for purposes of determining diluted earnings per share, includes the effects of dilutive restricted stock units, stock options and convertible securities. The effect of such potential common stock is computed using the treasury stock method or the if-converted method, as applicable.

Contingencies Contingencies (Po

Contingencies Contingencies (Policies)	12 Months Ended
	Dec. 31, 2017
Loss Contingencies [Line Items]
Commitments and Contingencies, Policy [Policy Text Block]	The Company is involved in certain claims, suits and legal proceedings in the normal course of business. The Company accrues for litigation and claims when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. The Company has recognized aggregate liabilities for all claims of approximately $50 million and $59 million as of December 31, 2017 and 2016 , respectively. These amounts are reported on the Consolidated Balance Sheets within Accrued and other liabilities and Other noncurrent liabilities . A significant portion of these accrued liabilities relate to regulatory matters and commercial disputes in international jurisdictions. There can be no assurance that these accrued liabilities will be adequate to cover all existing and future claims or that we will have the liquidity to pay such claims as they arise.

Segments and Geographic Informa

Segments and Geographic Information Segments and Geographic Information (Policies)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Segment Reporting, Policy [Policy Text Block]	The segment reporting structure uses the Company's organizational structure as its foundation to reflect how the Company manages the businesses internally and is organized by geographic regions which provides a socio-political-economic understanding of our business. During the third quarter of 2017, the Europe and Asia SBUs were merged in order to leverage scale and are now reported as part of the Eurasia SBU. The management reporting structure is organized by five SBUs led by our President and Chief Executive Officer: US, Andes, Brazil, MCAC and Eurasia SBUs. The Company determined that it has five operating and five reportable segments corresponding to its SBUs. All prior period results have been retrospectively revised to reflect the new segment reporting structure. In February 2018, we announced a reorganization as a part of our ongoing strategy to simplify our portfolio, optimize our cost structure, and reduce our carbon intensity. The Company is currently evaluating the impact this reorganization will have on our segment reporting structure. Corporate and Other — Corporate overhead costs which are not directly associated with the operations of our five reportable segments are included in "Corporate and Other." Also included are certain intercompany charges such as self-insurance premiums which are fully eliminated in consolidation. The Company uses Adjusted PTC as its primary segment performance measure. Adjusted PTC, a non-GAAP measure, is defined by the Company as pre-tax income from continuing operations attributable to The AES Corporation excluding gains or losses of the consolidated entity due to (a) unrealized gains or losses related to derivative transactions; (b) unrealized foreign currency gains or losses; (c) gains, losses and associated benefits and costs due to dispositions and acquisitions of business interests, including early plant closures; (d) losses due to impairments; (e) gains, losses and costs due to the early retirement of debt; and (f) costs directly associated with a major restructuring program, including, but not limited to, workforce reduction efforts, relocations, and office consolidation . Adjusted PTC also includes net equity in earnings of affiliates on an after-tax basis adjusted for the same gains or losses excluded from consolidated entities. The Company has concluded Adjusted PTC better reflects the underlying business performance of the Company and is the most relevant measure considered in the Company's internal evaluation of the financial performance of its segments. Additionally, given its large number of businesses and complexity, the Company concluded that Adjusted PTC is a more transparent measure that better assists investors in determining which businesses have the greatest impact on the Company's results. Revenue and Adjusted PTC are presented before inter-segment eliminations, which includes the effect of intercompany transactions with other segments except for interest, charges for certain management fees, and the write-off of intercompany balances, as applicable. All intra-segment activity has been eliminated within the segment. Inter-segment activity has been eliminated within the total consolidated results.

Income Taxes Income Taxes (Poli

Income Taxes Income Taxes (Policies)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Tax, Policy [Policy Text Block]	INCOME TAXES — Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of the existing assets and liabilities, and their respective income tax bases. The Company establishes a valuation allowance when it is more likely than not that all or a portion of a deferred tax asset will not be realized. The Company's tax positions are evaluated under a more likely than not recognition threshold and measurement analysis before they are recognized for financial statement reporting. Uncertain tax positions have been classified as noncurrent income tax liabilities unless expected to be paid within one year. The Company's policy for interest and penalties related to income tax exposures is to recognize interest and penalties as a component of the provision for income taxes in the Consolidated Statements of Operations. The Company's policy for interest and penalties related to income tax exposures is to recognize interest and penalties as a component of the provision for income taxes in the Consolidated Statements of Operations.

Earnings Per Share Earnings Per

Earnings Per Share Earnings Per Share (Policies)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share, Policy [Policy Text Block]	Basic and diluted earnings per share are based on the weighted-average number of shares of common stock and potential common stock outstanding during the period. Potential common stock, for purposes of determining diluted earnings per share, includes the effects of dilutive restricted stock units, stock options and convertible securities. The effect of such potential common stock is computed using the treasury stock method or the if-converted method, as applicable.

General and Summary of Signif46

General and Summary of Significant Accounting Policies Effect of Change in Estimate (Tables)	12 Months Ended
	Dec. 31, 2017
Change in Accounting Estimate [Line Items]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The following table provides a brief description of recent accounting pronouncements that had and/or could have a material impact on the Company’s consolidated financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or are expected to have no material impact on the Company’s consolidated financial statements. New Accounting Standards Adopted ASU Number and Name Description Date of Adoption Effect on the financial statements upon adoption 2016-09, Compensation — Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting The standard simplifies the following aspects of accounting for share-based payments awards: accounting for income taxes, classification of excess tax benefits on the statement of cash flows, forfeitures, statutory tax withholding requirements, classification of awards as either equity or liabilities and classification of employee taxes paid on statement of cash flows when an employer withholds shares for tax-withholding purposes. January 1, 2017 The recognition of excess tax benefits in the provision for income taxes in the period when the awards vest or are settled, rather than in paid-in-capital in the period when the excess tax benefits are realized, resulted in a decrease of $31 million to deferred tax liabilities, offset by an increase to retained earnings. New Accounting Standards Issued But Not Yet Effective ASU Number and Name Description Date of Adoption Effect on the financial statements upon adoption 2018-02, Income Statement — Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from AOCI This amendment allows a reclassification of the stranded tax effects resulting from the implementation of the Tax Cuts and Jobs Act from AOCI to retained earnings. Because this amendment only relates to the reclassification of the income tax effects of the Tax Cuts and Jobs Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-12, Derivatives and Hedging (Topic 815): Targeted improvements to Accounting for Hedging Activities The standard updates the hedge accounting model to expand the ability to hedge nonfinancial and financial risk components, reduce complexity, and ease certain documentation and assessment requirements. When facts and circumstances are the same as at the previous quantitative test, a subsequent quantitative effectiveness test is not required. The standard also eliminates the requirement to separately measure and report hedge ineffectiveness. For cash flow hedges, this means that the entire change in the fair value of a hedging instrument will be recorded in other comprehensive income and amounts deferred will be reclassified to earnings in the same income statement line as the hedged item. Transition method: modified retrospective with the cumulative effect adjustment recorded to the opening balance of retained earnings as of the initial application date. Prospective for presentation and disclosures. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-11, Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815): Accounting for Certain Financial Instruments and Certain Mandatorily Redeemable Noncontrolling Interests Part 1 of this standard changes the classification of certain equity-linked financial instruments when assessing whether the instrument is indexed to an entity’s own stock. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-08, Receivables — Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities This standard shortens the period of amortization for the premium on certain callable debt securities to the earliest call date. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-05, Other Income — Gains and Losses from the Derecognition of Nonfinancial Assets (Topic 610-20) This standard clarifies the scope and application of ASC 610-20 on the sale, transfer, and derecognition of nonfinancial assets and in substance nonfinancial assets to non-customers, including partial sales. It also clarifies that the derecognition of businesses is under scope of ASC 810. The standard must be adopted concurrently with ASC 606, however an entity will not have to apply the same transition method as ASC 606. January 1, 2018. Early adoption is permitted only as of January 1, 2017. The Company does not expect any impact on its consolidated financial statements upon adoption of the standard, will adopt the standard on January 1, 2018, and plans to use the modified retrospective approach. 2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment This standard simplifies the accounting for goodwill impairment by removing the requirement to calculate the implied fair value. Instead, it requires that an entity records an impairment charge based on the excess of a reporting unit's carrying amount over its fair value. January 1, 2020. Early adoption is permitted as of January 1, 2017. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business The standard requires an entity to first evaluate whether substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets, and if that threshold is met, the set is not a business. As a second step, to be considered a business at least one substantive process should exist. The revised definition of a business will reduce the number of transactions that are accounted for as business combinations. Transition Method: prospective. January 1, 2018. Early adoption is permitted. This revised definition will reduce the number of transactions that are accounted for as a business, therefore, acquisitions and disposition would fall under a different accounting model. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (a consensus of the FASB Emerging Issues Task Force) This standard requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents, and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. January 1, 2018. Early adoption is permitted. The Company has performed a preliminary evaluation and expects an increase in cash provided by operating activities of approximately $5 million for 2017 and 2016 and a decrease of $5 million in 2015. Net cash used in investing activities are expected to decrease by approximately $150 million and $230 million for 2017 and 2015, respectively, with an increase of $10 million expected for 2016. 2016-13, Financial Instruments — Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments The standard updates the impairment model for financial assets measured at amortized cost. For trade and other receivables, held-to-maturity debt securities, loans and other instruments, entities will be required to use a new forward-looking "expected loss" model that generally will result in the earlier recognition of allowance for losses. For available-for-sale debt securities with unrealized losses, entities will measure credit losses as it is done today, except that the losses will be recognized as an allowance rather than a reduction in the amortized cost of the securities. Transition method: various. January 1, 2020. Early adoption is permitted only as of January 1, 2019. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2016-02, 2018-01, Leases (Topic 842) See discussion of the ASU below. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements and intends to adopt the standard as of January 1, 2019. 2014-09, 2015-14, 2016-08, 2016-10, 2016-12, 2016-20, 2017-10, 2017-13, Revenue from Contracts with Customers (Topic 606) See discussion of the ASU below. January 1, 2018. Early adoption is permitted only as of January 1, 2017. The Company will adopt the standard on January 1, 2018; see below for the evaluation of the impact of its adoption on the consolidated financial statements.
Schedule of Change in Accounting Estimate [Table Text Block]	.

Inventory (Tables)

Inventory (Tables)	12 Months Ended
	Dec. 31, 2017
Inventory Disclosure [Abstract]
Inventory Balance By Type	The following table summarizes the Company's inventory balances as of the dates indicated (in millions): December 31, 2017 2016 Fuel and other raw materials $ 284 $ 302 Spare parts and supplies 278 320 Total $ 562 $ 622

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Property, Pland and Equipment with Useful Life Classification	The following table summarizes the components of the electric generation and distribution assets and other property, plant and equipment (in millions) with their estimated useful lives (in years). The amounts are stated net of all prior asset impairment losses recognized. December 31, Estimated Useful Life 2017 2016 Electric generation and distribution facilities 8 - 40 $ 21,529 $ 22,337 Other buildings 5 - 71 1,971 1,906 Furniture, fixtures and equipment 2 - 32 284 303 Other 5 - 44 335 365 Total electric generation and distribution assets and other 24,119 24,911 Accumulated depreciation (7,942 ) (7,919 ) Net electric generation and distribution assets and other $ 16,177 $ 16,992
Interest Capitalized During Development And Construction	The following table summarizes depreciation expense (including the amortization of assets recorded under capital leases and the amortization of asset retirement obligations) and interest capitalized during development and construction on qualifying assets for the periods indicated (in millions): Years Ended December 31, 2017 2016 2015 Depreciation expense $ 1,005 $ 1,002 $ 958 Interest capitalized during development and construction 139 118 84
Net Asset Value Of Regulated And Non-Regulated Assets And Accumulated Depreciation	The following table summarizes regulated and non-regulated generation and distribution property, plant and equipment and accumulated depreciation as of the dates indicated (in millions): December 31, 2017 2016 Regulated generation, distribution assets and other, gross $ 8,093 $ 7,815 Regulated accumulated depreciation (3,357 ) (3,299 ) Regulated generation, distribution assets and other, net 4,736 4,516 Non-regulated generation, distribution assets and other, gross 16,026 17,096 Non-regulated accumulated depreciation (4,585 ) (4,620 ) Non-regulated generation, distribution assets and other, net 11,441 12,476 Net electric generation, distribution assets and other $ 16,177 $ 16,992
Schedule of Change in Asset Retirement Obligation	The following table presents amounts recognized related to asset retirement obligations for the periods indicated (in millions): 2017 2016 Balance at January 1 $ 357 $ 247 Additional liabilities incurred 1 12 Liabilities settled (21 ) (4 ) Accretion expense 16 15 Change in estimated cash flows 25 86 Other (10 ) 1 Balance at December 31 $ 368 $ 357

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Significant unobservable inputs, recurring	The following table summarizes the significant unobservable inputs used for the Level 3 derivative assets (liabilities) as of December 31, 2017 (in millions, except range amounts): Type of Derivative Fair Value Unobservable Input Amount or Range (Weighted Average) Interest rate $ (151 ) Subsidiaries’ credit spreads 1.9% - 5.1% (4.9%) Foreign currency: Argentine peso 240 Argentine peso to U.S. dollar currency exchange rate after one year (1) 22.8 - 52.3 (36.6) Commodity: Other 4 Total $ 93
Derivatives Level 3 Rollforward Table	The following tables present a reconciliation of net derivative assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the years ended December 31, 2017 and 2016 (presented net by type of derivative in millions). Transfers between Level 3 and Level 2 are determined as of the end of the reporting period and principally result from changes in the significance of unobservable inputs used to calculate the credit valuation adjustment. Year Ended December 31, 2017 Interest Rate Foreign Currency Commodity Total Balance at January 1 $ (179 ) $ 255 $ 5 $ 81 Total realized and unrealized gains (losses): Included in earnings (1 ) 21 1 21 Included in other comprehensive income — derivative activity (23 ) — — (23 ) Included in regulatory liabilities — — 10 10 Settlements 36 (36 ) (12 ) (12 ) Transfers of liabilities into Level 3 (4 ) — — (4 ) Transfers of liabilities out of Level 3 20 — — 20 Balance at December 31 $ (151 ) $ 240 $ 4 $ 93 Total gains (losses) for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities held at the end of the period $ 7 $ (15 ) $ 1 $ (7 ) Year Ended December 31, 2016 Interest Rate Foreign Currency Commodity Total Balance at January 1 $ (304 ) $ 277 $ 3 $ (24 ) Total realized and unrealized gains (losses): Included in earnings — 31 2 33 Included in other comprehensive income — derivative activity (36 ) 6 — (30 ) Included in other comprehensive income — foreign currency translation activity 3 (52 ) — (49 ) Included in regulatory liabilities — — 11 11 Settlements 72 (22 ) (11 ) 39 Transfers of liabilities into Level 3 (32 ) — — (32 ) Transfers of assets out of Level 3 118 15 — 133 Balance at December 31 $ (179 ) $ 255 $ 5 $ 81 Total gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets and liabilities held at the end of the period $ 6 $ 16 $ 2 $ 24
Financial instruments not measured at fair value in the condensed consolidated balance sheets	The following table presents (in millions) the carrying amount, fair value and fair value hierarchy of the Company's financial assets and liabilities that are not measured at fair value in the Consolidated Balance Sheets as of the periods indicated, but for which fair value is disclosed. December 31, 2017 Carrying Amount Fair Value Total Level 1 Level 2 Level 3 Assets: Accounts receivable — noncurrent (1) $ 163 $ 217 $ — $ 6 $ 211 Liabilities: Non-recourse debt 15,340 15,890 — 13,350 2,540 Recourse debt 4,630 4,920 — 4,920 — December 31, 2016 Carrying Amount Fair Value Total Level 1 Level 2 Level 3 Assets: Accounts receivable — noncurrent (1) $ 232 $ 342 $ — $ 20 $ 322 Liabilities: Non-recourse debt 14,783 15,185 — 14,140 1,045 Recourse debt 4,671 4,899 — 4,899 — _____________________________ (1) These amounts primarily relate to amounts due from CAMMESA, the administrator of the wholesale electricity market in Argentina, and are included in Other noncurrent assets in the accompanying Consolidated Balance Sheets. The fair value and carrying amount of these receivables exclude VAT of $31 million and $24 million as of December 31, 2017 and 2016 , respectively.
Significant unobservable inputs, nonrecurring	The following table summarizes the significant unobservable inputs used in the Level 3 measurement of long-lived assets held and used measured on a nonrecurring basis during the year ended December 31, 2017 (in millions, except range amounts): December 31, 2017 Fair Value Valuation Technique Unobservable Input Range (Weighted Average) Long-lived assets held and used: Laurel Mountain $ 33 Discounted cash flow Annual revenue growth -30% to 2% (0%) Pre-tax operating margin (through remaining life) 61% to 73% (64%) Weighted-average cost of capital 9% Kilroot 20 Discounted cash flow Annual revenue growth -85% to 17% (-16%) Annual pre-tax operating margin -32% to 28% (6%) Weighted-average cost of capital 8% DPL 11 Discounted cash flow Pre-tax operating margin (through remaining life) 10% to 22% (15%) Weighted-average cost of capital 7% Total $ 64
Fair value hierarchy for nonrecurring measurements table	The following table summarizes major categories of assets and liabilities measured at fair value on a nonrecurring basis during the period and their level within the fair value hierarchy (in millions): Year Ended December 31, 2017 Measurement Date Carrying Amount (1) Fair Value Pre-tax Loss Assets Level 1 Level 2 Level 3 Long-lived assets held and used: (2) Laurel Mountain 12/31/2017 $ 154 $ — $ — $ 33 $ 121 Kilroot 12/31/2017 69 — — 20 37 DPL 02/28/2017 77 — — 11 66 Other Various 18 — — — 18 Dispositions and held-for-sale businesses: (3) DPL Peaker Assets 12/31/2017 346 — 237 — 109 Kazakhstan Hydroelectric (4) 06/30/2017 190 — 92 — 92 Kazakhstan CHPs 03/31/2017 171 — 29 — 94 Year Ended December 31, 2016 Measurement Date Carrying Amount (1) Fair Value Pre-tax Loss Assets Level 1 Level 2 Level 3 Long-lived assets held and used: (2) DPL 12/31/2016 $ 787 $ — $ 60 $ 103 $ 624 Buffalo Gap I 08/31/2016 113 — — 36 77 DPL 06/30/2016 324 — — 89 235 Buffalo Gap II 03/31/2016 251 — — 92 159 Discontinued operations: (3) Sul 06/30/2016 1,581 — 470 — 783 _____________________________ (1) Represents the carrying values at the dates of measurement, before fair value adjustment. (2) See Note 19 — Asset Impairment Expense for further information. (3) Per the Company's policy, pre-tax loss is limited to the impairment of long-lived assets. Any additional loss will be recognized on completion of the sale. Upon disposal of Sul, we incurred an additional pre-tax loss on sale of $602 million . See Note 21 — Discontinued Operations and Note 22 — Held-for-Sale Businesses and Dispositions for further information. (4) Per the Company's policy, pre-tax loss is limited to the impairment of long-lived assets. Any additional loss will be recognized on completion of the sale. Upon disposal of Kazakhstan HPPs, we incurred an additional pre-tax loss on disposal of $33 million . See Note 19 — Asset Impairment Expense and Note 22 — Held-for-Sale Businesses and Dispositions for further information. The foll
Fair value hierarchy for recurring measurements table	The following table presents, by level within the fair value hierarchy, as described in Note 1— General and Summary of Significant Accounting Policies , the Company's financial assets and liabilities that were measured at fair value on a recurring basis as of the dates indicated (in millions). For the Company's investments in marketable debt and equity securities, the security classes presented are determined based on the nature and risk of the security and are consistent with how the Company manages, monitors and measures its marketable securities: December 31, 2017 December 31, 2016 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets AVAILABLE FOR SALE: Debt securities: Unsecured debentures $ — $ 207 $ — $ 207 $ — $ 205 $ — $ 205 Certificates of deposit — 153 — 153 — 260 — 260 Government debt securities — — — — — 9 — 9 Subtotal — 360 — 360 — 474 — 474 Equity securities: Mutual funds — 52 — 52 — 48 — 48 Subtotal — 52 — 52 — 48 — 48 Total available for sale — 412 — 412 — 522 — 522 TRADING: Equity securities: Mutual funds 20 — — 20 16 — — 16 Total trading 20 — — 20 16 — — 16 DERIVATIVES: Interest rate derivatives — 15 — 15 — 18 — 18 Cross-currency derivatives — 29 — 29 — 4 — 4 Foreign currency derivatives — 29 240 269 — 54 255 309 Commodity derivatives — 30 5 35 — 38 7 45 Total derivatives — assets — 103 245 348 — 114 262 376 TOTAL ASSETS $ 20 $ 515 $ 245 $ 780 $ 16 $ 636 $ 262 $ 914 Liabilities DERIVATIVES: Interest rate derivatives $ — $ 111 $ 151 $ 262 $ — $ 121 $ 179 $ 300 Cross-currency derivatives — 3 — 3 — 18 — 18 Foreign currency derivatives — 30 — 30 — 64 — 64 Commodity derivatives — 19 1 20 — 40 2 42 Total derivatives — liabilities — 163 152 315 — 243 181 424 TOTAL LIABILITIES $ — $ 163 $ 152 $ 315 $ — $ 243 $ 181 $ 424
Available-for-sale Securities [Table Text Block]	The following table presents gross proceeds from sale of AFS securities for the periods indicated (in millions): Year Ended December 31, 2017 2016 2015 Gross proceeds from sales of AFS securities $ 1,398 $ 1,726 $ 1,226

Derivative Instruments and He50

Derivative Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Interest Rate Derivatives By Type Table	The following table presents the Company's maximum notional (in millions) over the remaining contractual period by type of derivative as of December 31, 2017 , regardless of whether they are in qualifying cash flow hedging relationships, and the dates through which the maturities for each type of derivative range: Derivatives Maximum Notional Translated to USD Latest Maturity Interest Rate (LIBOR and EURIBOR) $ 4,481 2036 Cross-Currency Swaps (Chilean Unidad de Fomento and Chilean Peso) 410 2029 Foreign Currency: Argentine Peso 187 2026 Chilean Peso 410 2020 Colombian Peso 305 2019 Others, primarily with weighted average remaining maturities of a year or less 303 2020
Derivative Assets Liabilities At Fair Value Net By Balance Sheet Classification And Type Table	The following tables present the fair value of assets and liabilities related to the Company's derivative instruments as of the periods indicated (in millions): Fair Value December 31, 2017 December 31, 2016 Assets Designated Not Designated Total Designated Not Designated Total Interest rate derivatives $ 15 $ — $ 15 $ 18 $ — $ 18 Cross-currency derivatives 29 — 29 4 — 4 Foreign currency derivatives 8 261 269 9 300 309 Commodity derivatives 5 30 35 20 25 45 Total assets $ 57 $ 291 $ 348 $ 51 $ 325 $ 376 Liabilities Interest rate derivatives $ 125 $ 137 $ 262 $ 295 $ 5 $ 300 Cross-currency derivatives 3 — 3 18 — 18 Foreign currency derivatives 1 29 30 19 45 64 Commodity derivatives 9 11 20 26 16 42 Total liabilities $ 138 $ 177 $ 315 $ 358 $ 66 $ 424 December 31, 2017 December 31, 2016 Fair Value Assets Liabilities Assets Liabilities Current $ 84 $ 211 $ 99 $ 155 Noncurrent 264 104 277 269 Total $ 348 $ 315 $ 376 $ 424 Credit Risk-Related Contingent Features (1) December 31, 2017 December 31, 2016 Present value of liabilities subject to collateralization $ 15 $ 41 Cash collateral held by third parties or in escrow 9 18 _____________________________ (1) Based on the credit rating of certain subsidiaries
Gain Loss In Accumulated Other Comprehensive Income And Earnings On Effective Portion Of Qualifying Cash Flow Hedges Table	The following table presents (in millions) the pre-tax gains (losses) recognized in AOCL and earnings related to all derivative instruments for the periods indicated: Years Ended December 31, 2017 2016 2015 Effective portion of cash flow hedges Gains (losses) recognized in AOCL Interest rate derivatives $ (66 ) $ (35 ) $ (103 ) Cross-currency derivatives 31 21 (20 ) Foreign currency derivatives (5 ) (4 ) 10 Commodity derivatives 18 30 40 Total $ (22 ) $ 12 $ (73 ) Gains (losses) reclassified from AOCL to earnings Interest rate derivatives $ (82 ) $ (101 ) $ (116 ) Cross-currency derivatives 34 8 (24 ) Foreign currency derivatives (20 ) (8 ) 32 Commodity derivatives 17 56 31 Total $ (51 ) $ (45 ) $ (77 ) Loss reclassified from AOCL to earnings due to discontinuance of hedge accounting (1) $ (13 ) $ — $ — Gain (losses) recognized in earnings related to Ineffective portion of cash flow hedges $ 3 $ (1 ) $ (6 ) Not designated as hedging instruments: Foreign currency derivatives $ 1 $ 19 $ 211 Commodity derivatives and other 14 (16 ) (29 ) Total $ 15 $ 3 $ 182

Financing Receivables (Tables)

Financing Receivables (Tables)	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Financing Receivables	The following table presents financing receivables by country as of the dates indicated (in millions): December 31, 2017 2016 Argentina $ 177 $ 236 Other 17 20 Total $ 194 $ 256

Investments In and Advances T52

Investments In and Advances To Affiliates (Tables)	12 Months Ended
	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Equity Ownership Interest And Carrying Values Of Investments Accounted For Under The Equity Method	The following table summarizes the relevant effective equity ownership interest and carrying values for the Company's investments accounted for under the equity method as of the periods indicated: December 31, 2017 2016 2017 2016 Affiliate Country Carrying Value (in millions) Ownership Interest % sPower United States $ 508 $ — 50 % — % Guacolda (1) Chile 357 362 33 % 33 % OPGC (2) India 269 195 49 % 49 % Elsta (3) Netherlands 38 41 50 % 50 % Equity method investments of Distributed Energy (3) United States 15 22 95 % 95 % Barry (3) United Kingdom — — 100 % 100 % Other affiliates Various 10 1 Total $ 1,197 $ 621 _____________________________ (1) The Company's ownership in Guacolda is held through AES Gener, a 67% -owned consolidated subsidiary. AES Gener owns 50% of Guacolda, resulting in an AES effective ownership in Guacolda of 33% . (2) OPGC has one coal-fired project under development which is an expansion of our existing OPGC business. The project started construction in April 2014 and is expected to begin operations in 2019. (3) Represent VIEs in which the Company holds a variable interest, but is not the primary beneficiary.
Investments In and Advances to Affiliates Financial Information	The following tables summarize financial information of the Company's 50%-or-less-owned affiliates and majority-owned unconsolidated subsidiaries that are accounted for using the equity method (in millions): 50%-or-less Owned Affiliates Majority-Owned Unconsolidated Subsidiaries Years ended December 31, 2017 2016 2015 2017 2016 2015 Revenue $ 762 $ 586 $ 641 $ 16 $ 23 $ 24 Operating margin 165 145 152 5 9 11 Net income (loss) 72 64 210 (15 ) (2 ) 6 December 31, 2017 2016 2017 2016 Current assets $ 418 $ 308 $ 70 $ 16 Noncurrent assets 5,372 2,577 102 181 Current liabilities 633 626 10 10 Noncurrent liabilities 2,629 1,209 147 122 Stockholders' equity 2,527 1,048 15 65

Goodwill and Other Intangible53

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table summarizes the carrying amount of goodwill by reportable segment for the years ended December 31, 2017 and 2016 (in millions): US Andes MCAC Eurasia Total Balance as of December 31, 2016 Goodwill $ 2,674 $ 899 $ 149 $ 190 $ 3,912 Accumulated impairment losses (2,633 ) — — (122 ) (2,755 ) Net balance 41 899 149 68 1,157 Transfer to assets held-for-sale (1) — (30 ) — (68 ) (98 ) Balance as of December 31, 2017 Goodwill 2,674 869 149 122 3,814 Accumulated impairment losses (2,633 ) — — (122 ) (2,755 ) Net balance $ 41 $ 869 $ 149 $ — $ 1,059 _____________________________ (1) See Note 22 --- Held-For-Sale Businesses and Dispositions for further information.
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets	The following table summarizes the balances comprising Other intangible assets in the accompanying Consolidated Balance Sheets (in millions) as of the periods indicated: December 31, 2017 December 31, 2016 Gross Balance Accumulated Amortization Net Balance Gross Balance Accumulated Amortization Net Balance Subject to Amortization Internal-use software $ 416 $ (330 ) $ 86 $ 396 $ (304 ) $ 92 Contracts 92 (21 ) 71 53 (15 ) 38 Contractual payment rights (1) 65 (47 ) 18 56 (42 ) 14 Project development rights 57 (1 ) 56 4 (1 ) 3 Other (2) 98 (42 ) 56 103 (37 ) 66 Subtotal 728 (441 ) 287 612 (399 ) 213 Indefinite-Lived Intangible Assets Land use rights 45 — 45 47 — 47 Water rights 20 — 20 17 — 17 Other 14 — 14 10 — 10 Subtotal 79 — 79 74 — 74 Total $ 807 $ (441 ) $ 366 $ 686 $ (399 ) $ 287 _____________________________ (1) Represent legal rights to receive system reliability payments from the regulator. (2) Includes management rights, sales concessions, gas extraction rights, and other individually insignificant intangible assets.
Schedule of Acquired Intangible Assets By Major Class	The following tables summarize other intangible assets acquired during the periods indicated (in millions): December 31, 2017 Amount Subject to Amortization/Indefinite-Lived Weighted Average Amortization Period (in years) Amortization Method Project Development Rights $ 53 Subject to Amortization 30 Straight-line Contracts 34 Subject to Amortization 25 Straight-line Internal-use software 17 Subject to Amortization 7 Straight-line Other 8 Various N/A N/A Total $ 112 December 31, 2016 Amount Subject to Amortization/Indefinite-Lived Weighted Average Amortization Period (in years) Amortization Method Internal-use software $ 41 Subject to Amortization 4 Straight-line Contracts 24 Subject to Amortization 26 Straight-line Other 5 Subject to Amortization 13 Straight-line Total $ 70
Schedule of Expected Amortization Expense	The following table summarizes the estimated amortization expense by intangible asset category for 2018 through 2022 : (in millions) 2018 2019 2020 2021 2022 Internal-use software $ 17 $ 14 $ 12 $ 10 $ 9 Contracts 5 5 5 5 5 Other 11 12 10 8 9 Total $ 33 $ 31 $ 27 $ 23 $ 23

Regulatory Assets and Liabili54

Regulatory Assets and Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Regulated Operations [Abstract]
Regulatory Assets and Liabilities	The Company has recorded regulatory assets and liabilities (in millions) that it expects to pass through to its customers in accordance with, and subject to, regulatory provisions as follows: December 31, 2017 2016 Recovery/Refund Period REGULATORY ASSETS Current regulatory assets: El Salvador tariff recoveries $ 59 $ 54 Quarterly as part of the tariff adjustment Other 60 34 Various Total current regulatory assets 119 88 Noncurrent regulatory assets: IPL and DPL defined benefit pension obligations (1) 298 316 Various IPL and DPL income taxes recoverable from customers (1) — 87 Various IPL deferred Midwest ISO costs 102 114 9 years IPL environmental costs 48 41 Various Other 94 97 Various Total noncurrent regulatory assets 542 655 TOTAL REGULATORY ASSETS $ 661 $ 743 REGULATORY LIABILITIES Current regulatory liabilities: DPL efficiency program costs $ 10 $ 14 Annually as part of the tariff adjustment Other 7 27 Various Total current regulatory liabilities 17 41 Noncurrent regulatory liabilities: IPL and DPL asset retirement obligations 830 795 Over life of assets IPL and DPL deferred income taxes 243 2 Various Other 6 5 Various Total noncurrent regulatory liabilities 1,079 802 TOTAL REGULATORY LIABILITIES $ 1,096 $ 843 _____________________________ (1) Past expenditures on which the Company earns a rate of return .
Schedule of Regulatory Assets by Region	The following table summarizes regulatory assets and liabilities by reportable segment in millions as of the periods indicated: December 31, 2017 December 31, 2016 Regulatory Assets Regulatory Liabilities Regulatory Assets Regulatory Liabilities US SBU $ 602 $ 1,095 $ 689 $ 842 MCAC SBU 59 — 54 — Brazil SBU — 1 — 1 Total $ 661 $ 1,096 $ 743 $ 843

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of Non-recourse debt [Table Text Block]	During the year ended December 31, 2017 , the Company's subsidiaries had the following significant debt transactions: Subsidiary Issuances Repayments Gain (Loss) on Extinguishment of Debt IPALCO $ 608 $ (528 ) $ (9 ) Tietê 585 (293 ) (5 ) Southland 557 — — Gener 335 (426 ) (20 ) AES Argentina 310 (181 ) 65 Los Mina 303 (275 ) (4 ) Colon 262 — — Masinloc 160 (51 ) — DPL 103 (249 ) (3 ) Other 285 (547 ) (1 ) Total $ 3,508 $ (2,550 ) $ 23
Carrying Amount and Terms of Non-Recourse Debt	The following table summarizes the carrying amount and terms of non-recourse debt at our subsidiaries as of the periods indicated (in millions): NON-RECOURSE DEBT Weighted Average Interest Rate Maturity December 31, 2017 2016 Variable Rate: (1) Bank loans 4.52% 2018 – 2050 $ 2,488 $ 2,601 Notes and bonds 8.06% 2020 – 2026 900 471 Debt to (or guaranteed by) multilateral, export credit agencies or development banks (2) 3.28% 2023 – 2034 3,668 3,189 Fixed Rate: Bank loans 4.54% 2018 – 2040 993 767 Notes and bonds 5.68% 2019 – 2073 7,388 7,822 Debt to (or guaranteed by) multilateral, export credit agencies or development banks (2) 5.35% 2023 – 2034 271 328 Other 5.81% 2018 – 2061 26 30 Unamortized (discount) premium & debt issuance (costs), net (394 ) (425 ) Subtotal $ 15,340 $ 14,783 Less: Current maturities (2,164 ) (1,052 ) Noncurrent maturities $ 13,176 $ 13,731 _____________________________ (1) The interest rate on variable rate debt represents the total of a variable component that is based on changes in an interest rate index and of a fixed component. The Company has interest rate swaps and option agreements in an aggregate notional principal amount of approximately $3.6 billion on non-recourse debt outstanding at December 31, 2017 . These agreements economically fix the variable component of the interest rates on the portion of the variable-rate debt being hedged so that the total interest rate on that debt has been fixed at rates ranging from approximately 2.49% to 8.00% . The debt agreements expire at various dates from 2018 through 2073 . (2) Multilateral loans include loans funded and guaranteed by bilaterals, multilaterals, development banks and other similar institutions.
Schedule For Maturity For Non-Recourse Debt	Non-recourse debt as of December 31, 2017 is scheduled to reach maturity as shown below (in millions): December 31, Annual Maturities 2018 $ 2,245 2019 796 2020 1,396 2021 1,833 2022 1,768 Thereafter 7,696 Unamortized (discount) premium & debt issuance (costs), net (394 ) Total $ 15,340
Debt In Default Table	The following table summarizes the Company's subsidiary non-recourse debt in default (in millions) as of December 31, 2017 . Due to the defaults, these amounts are included in the current portion of non-recourse debt: Primary Nature December 31, 2017 Subsidiary Default Net Assets Alto Maipo (Chile) Covenant $ 618 $ 352 AES Puerto Rico Covenant/Payment 365 692 AES Ilumina Covenant 36 54 Total $ 1,019
Schedule of Recourse Debt Detail	The following table summarizes the carrying amount and terms of recourse debt of the Company as of the periods indicated (in millions): Interest Rate Final Maturity December 31, 2017 December 31, 2016 Senior Unsecured Note LIBOR + 3.00% 2019 $ — $ 240 Senior Unsecured Note 8.00% 2020 228 469 Senior Unsecured Note 7.38% 2021 690 966 Drawings on secured credit facility LIBOR + 2.00% 2021 207 — Senior Secured Term Loan LIBOR + 2.00% 2022 521 — Senior Unsecured Note 4.88% 2023 713 713 Senior Unsecured Note 5.50% 2024 738 738 Senior Unsecured Note 5.50% 2025 573 573 Senior Unsecured Note 6.00% 2026 500 500 Senior Unsecured Note 5.13% 2027 500 — Term Convertible Trust Securities 6.75% 2029 — 517 Unamortized (discount) premium & debt issuance (costs), net (40 ) (45 ) Subtotal $ 4,630 $ 4,671 Less: Current maturities (5 ) — Noncurrent maturities $ 4,625 $ 4,671 December 31, Interest Rate Maturity 2017 2016 Senior Unsecured Note LIBOR + 3.00% 2019 $ — $ 240 Senior Unsecured Note 8.00% 2020 228 469 Senior Unsecured Note 7.38% 2021 690 966 Drawings on secured credit facility LIBOR + 2.00% 2021 207 — Senior Secured Term Loan LIBOR + 2.00% 2022 521 — Senior Unsecured Note 4.88% 2023 713 713 Senior Unsecured Note 5.50% 2024 738 738 Senior Unsecured Note 5.50% 2025 573 573 Senior Unsecured Note 6.00% 2026 500 500 Senior Unsecured Note 5.13% 2027 500 — Unamortized (discounts)/premiums & debt issuance (costs) (40 ) (45 ) Subtotal $ 4,630 $ 4,154 Less: Current maturities (5 ) — Total $ 4,625 $ 4,154
Schedule of Future Maturities of Recourse Debt	The following table summarizes the principal amounts due under our recourse debt for the next five years and thereafter (in millions): December 31, Net Principal Amounts Due 2018 $ 5 2019 5 2020 234 2021 902 2022 500 Thereafter 3,024 Unamortized (discount) premium & debt issuance (costs), net (40 ) Total recourse debt $ 4,630 As of December 31, 2017 scheduled maturities are presented in the following table (in millions): December 31, Annual Maturities 2018 $ 5 2019 5 2020 234 2021 902 2022 500 Thereafter 3,024 Unamortized (discount)/premium & debt issuance (costs) (40 ) Total debt $ 4,630

Commitments (Tables)

Commitments (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Operating Leases of Lessee Disclosure	The following table shows the future minimum lease payments under operating and capital leases for continuing operations together with the present value of the net minimum lease payments under capital leases as of December 31, 2017 for 2018 through 2022 and thereafter (in millions): Future Commitments for December 31, Capital Leases Operating Leases 2018 $ 2 $ 58 2019 1 58 2020 1 58 2021 1 59 2022 1 58 Thereafter 12 644 Total $ 18 $ 935 Less: Imputed interest (10 ) Present value of total minimum lease payments $ 8
Electricity Purchase Contract Commitment	The following table shows the future minimum commitments for continuing operations under these contracts as of December 31, 2017 for 2018 through 2022 and thereafter as well as actual purchases under these contracts for the years ended December 31, 2017 , 2016 , and 2015 (in millions): Actual purchases during the year ended December 31, Electricity Purchase Contracts Fuel Purchase Contracts Other Purchase Contracts 2015 $ 545 $ 1,262 $ 1,833 2016 420 1,790 817 2017 747 1,619 1,945 Future commitments for the year ending December 31, 2018 $ 581 $ 1,759 $ 1,488 2019 508 1,051 931 2020 440 591 470 2021 469 538 234 2022 438 454 547 Thereafter 2,065 1,466 1,314 Total $ 4,501 $ 5,859 $ 4,984

Contingencies (Tables)

Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Contingent Contractual Obligations	The following table summarizes the Parent Company's contingent contractual obligations as of December 31, 2017 . Amounts presented in the following table represent the Parent Company's current undiscounted exposure to guarantees and the range of maximum undiscounted potential exposure. The maximum exposure is not reduced by the amounts, if any, that could be recovered under the recourse or collateralization provisions in the guarantees. There were no obligations made by the Parent Company for the direct benefit of the lenders associated with the non-recourse debt of its businesses. Contingent Contractual Obligations Amount (in millions) Number of Agreements Maximum Exposure Range for Each Agreement (in millions) Guarantees and commitments $ 815 21 $1 — 272 Letters of credit under the unsecured credit facility 52 4 $2 — 26 Asset sale related indemnities (1) 27 1 27 Letters of credit under the senior secured credit facility 36 21 <$1 — 13 Total $ 930 47 _____________________________ (1) Excludes normal and customary representations and warranties in agreements for the sale of assets (including ownership in associated legal entities) where the associated risk is considered to be nominal.

Benefit Plans (Tables)

Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Schedule of Net Funded Status	The following table reconciles the Company's funded status, both domestic and foreign, as of the periods indicated (in millions): 2017 2016 U.S. Foreign U.S. Foreign CHANGE IN PROJECTED BENEFIT OBLIGATION: Benefit obligation as of January 1 $ 1,188 $ 411 $ 1,172 $ 374 Service cost 13 10 13 9 Interest cost 41 22 42 21 Employee contributions — 1 — 1 Plan amendments 1 (1 ) — (4 ) Plan curtailments 3 — 2 — Plan settlements — (2 ) — — Benefits paid (71 ) (22 ) (60 ) (19 ) Actuarial loss 82 29 19 58 Effect of foreign currency exchange rate changes — 22 — (29 ) Benefit obligation as of December 31 $ 1,257 $ 470 $ 1,188 $ 411 CHANGE IN PLAN ASSETS: Fair value of plan assets as of January 1 $ 1,044 $ 402 $ 1,021 $ 379 Actual return on plan assets 141 31 61 59 Employer contributions 13 18 22 18 Employee contributions — 1 — 1 Plan settlements — (2 ) — — Benefits paid (71 ) (22 ) (60 ) (19 ) Effect of foreign currency exchange rate changes — 27 — (36 ) Fair value of plan assets as of December 31 $ 1,127 $ 455 $ 1,044 $ 402 RECONCILIATION OF FUNDED STATUS Funded status as of December 31 $ (130 ) $ (15 ) $ (144 ) $ (9 )
Schedule of Amounts Recognized in Balance Sheet	The following table summarizes the amounts recognized on the Consolidated Balance Sheets related to the funded status of the DB Plans, both domestic and foreign, as of the periods indicated (in millions): December 31, 2017 2016 Amounts Recognized on the Consolidated Balance Sheets U.S. Foreign U.S. Foreign Noncurrent assets $ — $ 69 $ — $ 60 Accrued benefit liability—current — (6 ) — (5 ) Accrued benefit liability—noncurrent (130 ) (78 ) (144 ) (64 ) Net amount recognized at end of year $ (130 ) $ (15 ) $ (144 ) $ (9 )
Schedule of Accumulated and Projected Benefit Obligations	The following table summarizes the Company's U.S. and foreign accumulated benefit obligation as of the periods indicated (in millions): December 31, 2017 2016 U.S. Foreign U.S. Foreign Accumulated Benefit Obligation $ 1,236 $ 433 $ 1,167 $ 384 Information for pension plans with an accumulated benefit obligation in excess of plan assets: Projected benefit obligation $ 1,257 $ 109 $ 1,188 $ 90 Accumulated benefit obligation 1,236 97 1,167 80 Fair value of plan assets 1,127 33 1,044 25 Information for pension plans with a projected benefit obligation in excess of plan assets: Projected benefit obligation $ 1,257 $ 238 $ 1,188 $ 212 Fair value of plan assets 1,127 154 1,044 142
Schedule of Assumptions Used	The following table summarizes the significant weighted average assumptions used in the calculation of benefit obligation and net periodic benefit cost, both domestic and foreign, as of the periods indicated: December 31, 2017 2016 U.S. Foreign U.S. Foreign Benefit Obligation: Discount rate 3.67 % 5.23 % 4.28 % 5.83 % Rate of compensation increase 3.34 % 4.65 % 3.34 % 4.86 % Periodic Benefit Cost: Discount rate 4.28 % 5.83 % (1) 4.44 % 6.10 % (1) Expected long-term rate of return on plan assets 6.67 % 5.30 % 6.67 % 5.09 % Rate of compensation increase 3.34 % 4.86 % 3.34 % 4.45 % _____________________________ (1) Includes an inflation factor that is used to calculate future periodic benefit cost, but is not used to calculate the benefit obligation.
Impact Of One Percent Change In Assumptions	The impact on pension expense from a one percentage point change in these assumptions is shown in the following table (in millions): Increase of 1% in the discount rate $ (13 ) Decrease of 1% in the discount rate 12 Increase of 1% in the long-term rate of return on plan assets (15 ) Decrease of 1% in the long-term rate of return on plan assets 15
Schedule of Net Benefit Costs	The following table summarizes the components of the net periodic benefit cost, both domestic and foreign, for the years indicated (in millions): December 31, 2017 2016 2015 Components of Net Periodic Benefit Cost: U.S. Foreign U.S. Foreign U.S. Foreign Service cost $ 13 $ 10 $ 13 $ 9 $ 16 $ 10 Interest cost 41 23 42 21 48 23 Expected return on plan assets (69 ) (21 ) (68 ) (19 ) (70 ) (20 ) Amortization of prior service cost 6 — 7 (1 ) 7 — Amortization of net loss 18 2 18 2 20 2 Curtailment loss recognized 4 — 4 — — — Total pension cost $ 13 $ 14 $ 16 $ 12 $ 21 $ 15
Schedule of Net Periodic Benefit Cost Not yet Recognized	The following table summarizes in millions the amounts reflected in AOCL, including AOCL attributable to noncontrolling interests, on the Consolidated Balance Sheet as of December 31, 2017 , that have not yet been recognized as components of net periodic benefit cost and amounts expected to be reclassified to earnings in the next fiscal year (in millions): December 31, 2017 Accumulated Other Comprehensive Income (Loss) Amounts expected to be reclassified to earnings in next fiscal year U.S. Foreign U.S. Foreign Prior service cost $ (1 ) $ 1 $ — $ — Unrecognized net actuarial loss (22 ) (81 ) (2 ) (3 ) Total $ (23 ) $ (80 ) $ (2 ) $ (3 )
Target / Actual Allocation Of Pension Plan Asset	The following table summarizes the Company's target allocation for 2017 and pension plan asset allocation, both domestic and foreign, as of the periods indicated: Percentage of Plan Assets as of December 31, Target Allocations 2017 2016 Asset Category U.S. Foreign U.S. Foreign U.S. Foreign Equity securities 33% 4% 31.90 % 4.61 % 50.96 % 18.66 % Debt securities 65% 93% 64.53 % 93.10 % 45.88 % 78.35 % Real estate 2% —% 3.20 % 0.44 % 3.16 % 0.75 % Other —% 3% 0.37 % 1.85 % — % 2.24 % Total pension assets 100.00 % 100.00 % 100.00 % 100.00 %
Schedule of Allocation of Plan Assets	The asset allocation is reviewed periodically to determine a suitable asset allocation which seeks to manage risk through portfolio diversification and takes into account the above-stated objectives, in conjunction with current funding levels, cash flow conditions and economic and industry trends. The following table summarizes the Company's U.S. DB Plan assets by category of investment and level within the fair value hierarchy as of the periods indicated (in millions): December 31, 2017 December 31, 2016 U.S. Plans Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Equity securities: Mutual funds $ 359 $ — $ — $ 359 $ 532 $ — $ — $ 532 Debt securities: Government debt securities 135 — — 135 86 — — 86 Mutual funds (1) 593 — — 593 393 — — 393 Real estate: Real estate — 36 — 36 — 33 — 33 Other: Cash and cash equivalents 4 — — 4 — — — — Total plan assets $ 1,091 $ 36 $ — $ 1,127 $ 1,011 $ 33 $ — $ 1,044 _____________________________ (1) Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment
Fair Value Of Plan Assets By Category / Level (Foreign)	The investment strategy of the foreign DB Plans seeks to maximize return on investment while minimizing risk. The assumed asset allocation has less exposure to equities in order to closely match market conditions and near term forecasts. The following table summarizes the Company's foreign DB plan assets by category of investment and level within the fair value hierarchy as of the periods indicated (in millions): December 31, 2017 December 31, 2016 Foreign Plans Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Equity securities: Mutual funds $ 20 $ — $ — $ 20 $ 71 $ — $ — $ 71 Private equity — — 1 1 — — 4 4 Debt securities: Government debt securities 11 — — 11 10 — — 10 Mutual funds (1) 323 90 — 413 215 90 — 305 Real estate: Real estate — — 2 2 — — 3 3 Other: Participant loans (2) — — — — — — 2 2 Other assets 1 — 7 8 4 — 3 7 Total plan assets $ 355 $ 90 $ 10 $ 455 $ 300 $ 90 $ 12 $ 402 _____________________________ (1) Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment. (2) Loans to participants are stated at cost, which approximates fair value
Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets	.
Scheduled Cash Flows For Employer Contributions And Expected Future Benefit Payments	The following table summarizes the estimated cash flows for U.S. and foreign expected employer contributions and expected future benefit payments, both domestic and foreign (in millions): U.S. Foreign Expected employer contribution in 2018 $ 39 $ 15 Expected benefit payments for fiscal year ending: 2018 71 23 2019 73 23 2020 74 25 2021 75 26 2022 76 27 2023 - 2027 380 170

Equity (Tables)

Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Schedule of Net Income Attributable to Parent And Transfers To From Noncontrolling Interests [Text Block]	The following table summarizes the net income attributable to The AES Corporation and all transfers (to) from noncontrolling interests for the periods indicated (in millions): December 31, 2017 2016 2015 Net income (loss) attributable to The AES Corporation $ (1,161 ) $ (1,130 ) $ 306 Transfers from noncontrolling interest: Net increase in The AES Corporation's paid-in capital for sale of subsidiary shares 13 84 323 Additional paid-in-capital, IPALCO shares, transferred to redeemable stock of subsidiaries (1) — (84 ) (377 ) Increase (decrease) in The AES Corporation's paid-in-capital for purchase of subsidiary shares 240 (2 ) — Net transfers (to) from noncontrolling interest 253 (2 ) (54 ) Change from net income (loss) attributable to The AES Corporation and transfers (to) from noncontrolling interests $ (908 ) $ (1,132 ) $ 252 _____________________________ (1) See Note 17 — Redeemable stock of subsidiaries for further information on increase in paid-in-capital transferred to redeemable stock of subsidiaries.
Components of Accumulated Other Comprehensive Income	The changes in AOCL by component, net of tax and noncontrolling interests, for the periods indicated were as follows (in millions): Foreign currency translation adjustment, net Unrealized derivative losses, net Unfunded pension obligations, net Total Balance at December 31,2015 $ (3,256 ) $ (353 ) $ (274 ) $ (3,883 ) Other comprehensive income (loss) before reclassifications 117 2 (13 ) 106 Amount reclassified to earnings 992 28 1 1,021 Other comprehensive income (loss) $ 1,109 $ 30 $ (12 ) $ 1,127 Balance at December 31, 2016 $ (2,147 ) $ (323 ) $ (286 ) $ (2,756 ) Other comprehensive loss before reclassifications $ 18 $ (14 ) $ (19 ) $ (15 ) Amount reclassified to earnings 643 37 248 928 Other comprehensive income $ 661 $ 23 $ 229 $ 913 Reclassification from NCI due to Alto Maipo Restructuring — (33 ) — (33 ) Balance at December 31, 2017 $ (1,486 ) $ (333 ) $ (57 ) $ (1,876 )
Reclassification out of Accumulated Other Comprehensive Income	Reclassifications out of AOCL are presented in the following table. Amounts for the periods indicated are in millions and those in parenthesis indicate debits to the Condensed Consolidated Statements of Operations: Details About December 31, AOCL Components Affected Line Item in the Consolidated Statements of Operations 2017 2016 2015 Foreign currency translation adjustments, net Gain (loss) on disposal and sale of businesses $ (188 ) $ — $ — Net loss from disposal and impairments of discontinued operations (455 ) (992 ) — Net income (loss) attributable to The AES Corporation $ (643 ) $ (992 ) $ — Unrealized derivative gains (losses), net Non-regulated revenue $ 25 $ 111 $ 43 Non-regulated cost of sales (12 ) (57 ) (14 ) Interest expense (79 ) (107 ) (112 ) Gain (loss) on disposal and sale of businesses — — (4 ) Foreign currency transaction gains 15 8 12 Income from continuing operations before taxes and equity in earnings of affiliates (51 ) (45 ) (75 ) Income tax expense 1 8 11 Net equity in earnings of affiliates — — (2 ) Income (loss) from continuing operations (50 ) (37 ) (66 ) Less: (Income) from continuing operations attributable to noncontrolling interests 13 9 18 Net income (loss) attributable to The AES Corporation $ (37 ) $ (28 ) $ (48 ) Amortization of defined benefit pension actuarial losses, net Non-regulated cost of sales 1 — 2 General and administrative expenses (1 ) (1 ) (2 ) Other expense — (1 ) — Income from continuing operations before taxes and equity in earnings of affiliates — (2 ) — Income tax expense — 3 9 Income from continuing operations — 1 9 Net loss from disposal and impairments of discontinued operations (266 ) (11 ) (25 ) Net income (loss) (266 ) (10 ) (16 ) Less: (Income) from continuing operations attributable to noncontrolling interests — 9 14 Add: Loss from discontinued operations attributable to noncontrolling interests 18 — — Net income (loss) attributable to The AES Corporation $ (248 ) $ (1 ) $ (2 ) Total reclassifications for the period, net of income tax and noncontrolling interests $ (928 ) $ (1,021 ) $ (50 )

Segment and Geographic Inform60

Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting Information [Line Items]
Schedule of Segment Reporting Information, by Segment [Table Text Block]	The following tables present financial information by segment for the periods indicated (in millions): Total Revenue Year Ended December 31, 2017 2016 2015 US SBU $ 3,229 $ 3,429 $ 3,593 Andes SBU 2,710 2,506 2,489 Brazil SBU 542 450 962 MCAC SBU 2,448 2,172 2,353 Eurasia SBU 1,590 1,670 1,875 Corporate and Other 35 77 31 Eliminations (24 ) (23 ) (43 ) Total Revenue $ 10,530 $ 10,281 $ 11,260 Reconciliation from Income from Continuing Operations before Taxes and Equity in Earnings of Affiliates: Total Adjusted PTC Year Ended December 31, 2017 2016 2015 Income from continuing operations before taxes and equity in earnings of affiliates $ 771 $ 187 $ 989 Add: Net equity earnings in affiliates 71 36 105 Less: Income from continuing operations before taxes, attributable to noncontrolling interests (521 ) (354 ) (513 ) Pre-tax contribution 321 (131 ) 581 Unrealized derivative gains (3 ) (9 ) (166 ) Unrealized foreign currency (gains) losses (59 ) 22 95 Disposition/acquisition (gains) losses 123 6 (42 ) Impairment losses 542 933 504 Loss on extinguishment of debt 62 29 179 Restructuring costs (1) 31 — — Total Adjusted PTC $ 1,017 $ 850 $ 1,151 _____________________________ (1) One-time restructuring charges consisting of severance costs related to workforce reductions. Total Adjusted PTC Year Ended December 31, 2017 2016 2015 US SBU $ 361 $ 347 $ 360 Andes SBU 386 390 482 Brazil SBU 60 38 92 MCAC SBU 340 267 327 Eurasia SBU 290 283 331 Corporate and Other (420 ) (475 ) (441 ) Total Adjusted PTC $ 1,017 $ 850 $ 1,151 Total Assets Depreciation and Amortization Capital Expenditures Year Ended December 31, 2017 2016 2015 2017 2016 2015 2017 2016 2015 US SBU $ 9,852 $ 9,333 $ 9,800 $ 437 $ 471 $ 443 $ 858 $ 809 $ 861 Andes SBU 8,840 8,971 8,594 250 218 175 443 538 949 Brazil SBU 2,034 1,516 1,179 51 33 39 34 31 47 MCAC SBU 5,532 5,162 4,820 172 165 155 482 480 201 Eurasia SBU 4,557 5,777 6,200 127 149 166 211 279 131 Assets of discontinued operations and held-for-sale businesses 2,034 4,936 5,411 123 128 146 315 303 252 Corporate and Other 263 429 541 9 12 20 13 18 17 Total $ 33,112 $ 36,124 $ 36,545 $ 1,169 $ 1,176 $ 1,144 $ 2,356 $ 2,458 $ 2,458 Interest Income Interest Expense Year Ended December 31, 2017 2016 2015 2017 2016 2015 US SBU $ — $ — $ — $ 258 $ 236 $ 262 Andes SBU 50 57 77 205 178 154 Brazil SBU 45 38 31 92 69 58 MCAC SBU 18 11 30 168 163 179 Eurasia SBU 130 139 116 167 179 158 Corporate and Other 1 — 2 280 309 334 Total $ 244 $ 245 $ 256 $ 1,170 $ 1,134 $ 1,145 Investments in and Advances to Affiliates Net Equity in Earnings of Affiliates Year Ended December 31, 2017 2016 2015 2017 2016 2015 US SBU $ 527 $ 23 $ 1 $ 41 $ 9 $ — Andes SBU 358 363 345 28 15 83 MCAC SBU 3 (1 ) — (4 ) (2 ) — Eurasia SBU 307 236 248 9 13 18 Corporate and Other 2 — 16 (3 ) 1 4 Total $ 1,197 $ 621 $ 610 $ 71 $ 36 $ 105
Revenue And PP&E By Country	The following table presents information, by country, about the Company's consolidated operations for each of the three years ended December 31, 2017 , 2016 , and 2015 , and as of December 31, 2017 and 2016 (in millions). Revenue is recorded in the country in which it is earned and assets are recorded in the country in which they are located. Total Revenue Property, Plant & Equipment, net Year Ended December 31, 2017 2016 2015 2017 2016 United States $ 3,240 $ 3,489 $ 3,597 $ 7,403 $ 7,397 Non-U.S.: Chile 1,944 1,707 1,523 5,066 4,995 Dominican Republic 826 614 632 935 914 El Salvador 686 601 736 340 327 Brazil 541 450 962 1,286 789 Philippines 449 401 406 — 866 Argentina 435 359 399 223 195 Bulgaria 367 334 382 1,290 1,174 Mexico 352 342 383 687 699 Panama 338 312 297 1,615 1,233 Colombia 332 437 557 332 451 United Kingdom 328 337 396 108 151 Vietnam (1) 278 340 233 2 1 Puerto Rico 247 301 302 565 583 Jordan 95 136 248 431 452 Kazakhstan 67 103 155 — 178 Other Non-U.S. 5 18 52 13 10 Total Non-U.S. 7,290 6,792 7,663 12,893 13,018 Total $ 10,530 $ 10,281 $ 11,260 $ 20,296 $ 20,415

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	N
Schedule of Share Based Compensation Summary of Financial Statement Components Stock Options	N
Schedule of Share-based Compensation, Stock Options, Activity	N
Schedule of Share Based Compensation Summary of Financial Statement Components Restricted Stock Units Without Market Conditions	The following table summarizes the components of the Company's stock-based compensation related to its employee RSUs recognized in the Company's consolidated financial statements (in millions): December 31, 2017 2016 2015 RSU expense before income tax $ 17 $ 14 $ 13 Tax benefit (4 ) (4 ) (3 ) RSU expense, net of tax $ 13 $ 10 $ 10 Total value of RSUs converted (1) $ 10 $ 7 $ 16 Total fair value of RSUs vested $ 15 $ 13 $ 12 _____________________________ (1) Amount represents fair market value on the date of conversion.
Schedule of Share Based Compensation Restricted Stock Units Without Market Conditions Activity Table	A summary of the activity of RSUs for the year ended December 31, 2017 follows (RSUs in thousands): RSUs Weighted Average Grant Date Fair Values Weighted Average Remaining Vesting Term Non-vested at December 31, 2016 3,037 $ 10.70 Vested (1,337 ) 11.37 Forfeited and expired (280 ) 10.94 Granted 1,546 11.93 Non-vested at December 31, 2017 2,966 $ 11.02 1.4 Vested and expected to vest at December 31, 2017 2,711 $ 11.01
Schedule of Share Based Compensation Restricted Stock Units Without Market Condition Vested And Converted	The following table summarizes the RSUs that vested and were converted during the periods indicated (RSUs in thousands): Year Ended December 31, 2017 2016 2015 RSUs vested during the year 1,337 1,063 954 RSUs converted during the year, net of shares withheld for taxes 865 705 1,238 Shares withheld for taxes 472 358 549
Schedule of Share Based Compensation Summary of Financial Statement Components Restricted Stock Units With Market Conditions	.
Schedule of Share Based Compensation Restricted Stock Units With Market Conditions Activity	.
Schedule of Share Based Compensation Restricted Stock Units With Market Condition Vested and Converted

Redeemable Stock of Subsidiar62

Redeemable Stock of Subsidiaries Redeemable Stock of Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2017
Temporary Equity Disclosure [Abstract]
Redeemable Noncontrolling Interest [Table Text Block]	The following table summarizes the Company's redeemable stock of subsidiaries balances as of the periods indicated (in millions): December 31, 2017 2016 IPALCO common stock $ 618 $ 618 Colon quotas (1) 159 100 IPL preferred stock 60 60 Other common stock — 4 Total redeemable stock of subsidiaries $ 837 $ 782 _____________________________ (1) Characteristics of quotas are similar to common stock. The following table is a reconciliation of changes in redeemable stock of subsidiaries (in millions): December 31, 2017 2016 Balance at the beginning of the period $ 782 $ 538 Sale of redeemable stock of subsidiaries — 134 Contributions from holders of redeemable stock of subsidiaries 50 130 Net loss attributable to redeemable stock of subsidiaries (14 ) (11 ) Fair value adjustment (1) 25 4 Other comprehensive income (loss) attributable to redeemable stock of subsidiaries (2 ) 6 Acquisition and reclassification of stock of subsidiaries (4 ) (19 ) Balance at the end of the period $ 837 $ 782 _____________________________ (1) $5 million increase in fair value of DP&L preferred shares offset by $1 million decrease in fair value of Colon common stock in 2016.

Other Income and Expense (Table

Other Income and Expense (Tables)	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Components of Other Income	The components are summarized as follows (in millions): Year Ended December 31, 2017 2016 2015 Legal settlements (1) $ 60 $ — $ — Allowance for funds used during construction (US Utilities) 26 29 17 Gain on sale of assets 1 4 17 Contract termination — — 20 Other 33 31 30 Total other income $ 120 $ 64 $ 84
Components of Other Expense	The components are summarized as follows (in millions): Year Ended December 31, 2017 2016 2015 Allowance for other receivables (1) $ — $ 52 $ — Loss on sale and disposal of assets 28 12 — Water rights write-off 19 6 10 Other 10 9 14 Total other expense $ 57 $ 79 $ 24 _____________________________ (1) During the fourth quarter of 2016, we recognized a full allowance on a non-trade receivable in the MCAC SBU as a result of payment delays and discussions with the counterparty. The allowance relates to certain reimbursements the Company was expecting in connection with a legal matter. Management believes the counterparty is obligated to pay and plans to continue to attempt to fully collect the non-trade receivable.

Asset Impairment Expense (Table

Asset Impairment Expense (Tables)	12 Months Ended
	Dec. 31, 2017
Impairment or Disposal of Tangible Assets Disclosure [Abstract]
Details of Impairment of Long-Lived Assets Held and Used by Asset	Year ended December 31, (in millions) 2017 2016 2015 DPL $ 175 $ 859 $ — Laurel Mountain 121 — — Kazakhstan Hydroelectric 92 — — Kazakhstan CHPs 94 — — Kilroot 37 — 121 Buffalo Gap II — 159 — Buffalo Gap I — 77 — Buffalo Gap III — — 116 U.K. Wind — — 37 Other 18 1 11 Total $ 537 $ 1,096 $ 285

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Tax Expense On Continuing Operations	The following table summarizes the expense for income taxes on continuing operations for the periods indicated (in millions): December 31, 2017 2016 2015 Federal: Current $ — $ 2 $ 9 Deferred 545 (361 ) (63 ) State: Current — 1 1 Deferred 1 (4 ) (5 ) Foreign: Current 335 318 470 Deferred 109 76 — Total $ 990 $ 32 $ 412
Reconciliation Of US Federal Income Tax Rates And AES Effective Tax Rate For The Current And Two Prior Years	The following table summarizes a reconciliation of the U.S. statutory federal income tax rate to the Company's effective tax rate as a percentage of income from continuing operations before taxes for the periods indicated: December 31, 2017 2016 2015 Statutory Federal tax rate 35 % 35 % 35 % State taxes, net of Federal tax benefit (7 )% (18 )% (6 )% Taxes on foreign earnings — % (46 )% 5 % Valuation allowance 10 % 10 % (5 )% Uncertain tax positions — % 4 % (1 )% Noncontrolling Interest on Buffalo Gap impairments — % 31 % 3 % Change in tax law 90 % 12 % — % Goodwill impairment — % — % 11 % Other—net — % (11 )% — % Effective tax rate 128 % 17 % 42 %
Schedule Of Income Tax Payable And Receivable	The following table summarizes the income taxes receivable and payable as of the periods indicated (in millions): December 31, 2017 2016 Income taxes receivable—current $ 147 $ 136 Total income taxes receivable $ 147 $ 136 Income taxes payable—current $ 129 $ 149 Income taxes payable—noncurrent 17 22 Total income taxes payable $ 146 $ 171
Summary Of Deferred Tax Assets And Liabilities	The following table summarizes deferred tax assets and liabilities, as of the periods indicated (in millions): December 31, 2017 2016 Differences between book and tax basis of property $ (1,424 ) $ (1,926 ) Other taxable temporary differences (143 ) (335 ) Total deferred tax liability (1,567 ) (2,261 ) Operating loss carryforwards 1,439 2,088 Capital loss carryforwards 63 59 Bad debt and other book provisions 66 96 Tax credit carryforwards 51 54 Other deductible temporary differences 60 263 Total gross deferred tax asset 1,679 2,560 Less: valuation allowance (988 ) (876 ) Total net deferred tax asset 691 1,684 Net deferred tax (liability) $ (876 ) $ (577 )
Income Before Income Taxes, Foreign And Domestic	The following table shows the income (loss) from continuing operations, before income taxes, net equity in earnings of affiliates and noncontrolling interests, for the periods indicated (in millions): December 31, 2017 2016 2015 U.S. $ (511 ) $ (1,305 ) $ (612 ) Non-U.S. 1,282 1,492 1,601 Total $ 771 $ 187 $ 989
Uncertain Tax Positions [Table Text Block]	The following table shows the total amount of gross accrued income taxes related to interest and penalties included in the Consolidated Balance Sheets for the periods indicated (in millions): December 31, 2017 2016 Interest related $ 7 $ 6 Penalties related — — The following table shows the expense/(benefit) related to interest and penalties on unrecognized tax benefits for the periods indicated (in millions): December 31, 2017 2016 2015 Total expense (benefit) for interest related to unrecognized tax benefits $ 1 $ 2 $ (2 ) Total expense for penalties related to unrecognized tax benefits — — —
Tax Years Potentially Subject To Examination And Jurisdictions	The following is a summary of tax years potentially subject to examination in the significant tax and business jurisdictions in which we operate: Jurisdiction Tax Years Subject to Examination Argentina 2011-2017 Brazil 2012-2017 Chile 2014-2017 Colombia 2015-2017 Dominican Republic 2015-2017 El Salvador 2014-2017 Netherlands 2014-2017 Philippines 2013-2017 United Kingdom 2012-2017 United States (Federal) 2014-2017
Unrecognized Tax Benefits	The following is a reconciliation of the beginning and ending amounts of unrecognized tax benefits for the periods indicated (in millions): December 31, 2017 2016 2015 Balance at January 1 $ 352 $ 364 $ 384 Additions for current year tax positions — 2 2 Additions for tax positions of prior years 2 1 12 Reductions for tax positions of prior years (5 ) (1 ) (7 ) Effects of foreign currency translation — — (3 ) Settlements — (13 ) (17 ) Lapse of statute of limitations (1 ) (1 ) (7 ) Balance at December 31 $ 348 $ 352 $ 364

Discontinued Operations and Hel

Discontinued Operations and Held-For-Sale Businesses (Tables)	12 Months Ended
	Dec. 31, 2017
Discontinued Operations [Abstract]
Disposal Groups, Including Discontinued Operations [Table Text Block]	egment. The following table summarizes the carrying amounts of the major classes of assets and liabilities of discontinued operations at December 31, 2017 and December 31, 2016 : (in millions) December 31, 2017 December 31, 2016 Assets of discontinued operations and held-for-sale businesses: Cash and cash equivalents $ — $ 61 Short-term investments — 268 Accounts receivable, net of allowance for doubtful accounts of $0 and $94, respectively — 745 Other current assets — 499 Property, plant and equipment and intangibles, net — 2,504 Investments in and advances to affiliates (1) 86 — Deferred income taxes — 554 Other classes of assets that are not major — 305 Total assets of discontinued operations $ 86 $ 4,936 Other assets of businesses classified as held-for-sale (2) 1,948 — Total assets of discontinued operations and held-for-sale businesses (3) $ 2,034 $ 4,936 Liabilities of discontinued operations and held-for-sale businesses: Accounts payable $ — $ 418 Accrued and other liabilities — 954 Non-recourse debt — 1,009 Pension and other postretirement liabilities — 1,159 Other noncurrent liabilities — 678 Other classes of liabilities that are not major — 31 Total liabilities of discontinued operations $ — $ 4,249 Other liabilities of businesses classified as held-for-sale (2) 1,033 — Total liabilities of discontinued operations and held-for-sale businesses (3) $ 1,033 $ 4,249 _____________________________ (1) Represents the Company's 17% ownership interest in Eletropaulo. (2) Masinloc, Eletrica Santiago, and the DPL peaker assets were classified as held-for-sale as of December 31, 2017 . See Note 22 — Held-for-Sale Businesses and Dispositions for further information. (3) Amounts at December 31, 2016 are classified as both current and long-term on the Consolidated Balance Sheet. The following table summarizes the major line items constituting losses from discontinued operations for the periods indicated (in millions): December 31, 2017 2016 2015 Income (loss) from discontinued operations, net of tax: Revenue — regulated $ 3,320 $ 4,036 $ 4,430 Cost of sales (3,151 ) (3,954 ) (4,227 ) Other income and expense items that are not major (1) (166 ) (160 ) (70 ) Income (loss) from operations of discontinued businesses 3 (78 ) 133 Loss from disposal and impairments of discontinued businesses (611 ) (1,385 ) — Income (loss) from discontinued operations (608 ) (1,463 ) 133 Less: Net income attributable to noncontrolling interests (25 ) (142 ) (92 ) Income (loss) from discontinued operations attributable to The AES Corporation (633 ) (1,605 ) 41 Income tax benefit (expense) (21 ) 495 (53 ) Loss from discontinued operations, net of tax $ (654 ) $ (1,110 ) $ (12 ) _____________________________ (1) Includes a loss contingency recognized by our equity method investment in discontinued operations. The following table summarizes the operating and investing cash flows from discontinued operations for the periods indicated (in mill

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share Basic And Diluted Table	The following table is a reconciliation of the numerator and denominator of the basic and diluted earnings per share computation for income from continuing operations for the years ended December 31, 2017 , 2016 and 2015 , where income represents the numerator and weighted-average shares represent the denominator. Values are in millions except per share data: Year Ended December 31, 2017 2016 2015 Loss Shares $ per Share Loss Shares $ per Share Income Shares $ per Share BASIC EARNINGS PER SHARE Income (loss) from continuing operations attributable to The AES Corporation common stockholders (1) $ (507 ) 660 $ (0.77 ) $ (25 ) 660 $ (0.04 ) $ 318 687 $ 0.46 EFFECT OF DILUTIVE SECURITIES Restricted stock units — — — — — — — 2 — DILUTED EARNINGS PER SHARE $ (507 ) 660 $ (0.77 ) $ (25 ) 660 $ (0.04 ) $ 318 689 $ 0.46 _____________________________ (1) Loss from continuing operations, net of tax, of $20 million less the $5 million adjustment to retained earnings to record the DP&L redeemable preferred stock at its redemption value as of December 31, 2016 .

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	The Company's Consolidated Statements of Operations included the following transactions with related parties for the periods indicated (in millions): Years Ended December 31, 2017 2016 2015 Revenue—Non-Regulated $ 1,297 $ 1,100 $ 1,099 Cost of Sales—Non-Regulated 220 210 330 Interest income 8 4 25 Interest expense 36 39 33
Schedule of Related Party Receivables Payables	The following table summarizes the balances receivable from and payable to related parties included in the Company's Consolidated Balance Sheets as of the periods indicated (in millions): December 31, 2017 2016 Receivables from related parties $ 250 $ 218 Accounts and notes payable to related parties 727 892

Selected Quarterly Financial 69

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	The following tables summarize the unaudited quarterly Condensed Consolidated Statements of Operations for the Company for 2017 and 2016 (amounts in millions, except per share data). Amounts have been restated to reflect discontinued operations in all periods presented and reflect all adjustments necessary in the opinion of management for a fair statement of the results for interim periods. Quarter Ended 2017 Mar 31 June 30 Sept 30 Dec 31 Revenue $ 2,581 $ 2,613 $ 2,693 $ 2,643 Operating margin 554 625 642 643 Income (loss) from continuing operations, net of tax (1) 97 141 236 (622 ) Income (loss) from discontinued operations, net of tax 1 9 25 (664 ) Net income (loss) $ 98 $ 150 $ 261 $ (1,286 ) Net income (loss) attributable to The AES Corporation $ (24 ) $ 53 $ 152 $ (1,342 ) Basic income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.04 $ 0.08 $ 0.22 $ (1.03 ) Income (loss) from discontinued operations attributable to The AES Corporation common stockholders, net of tax — — 0.01 (1.00 ) Basic income (loss) per share attributable to The AES Corporation $ 0.04 $ 0.08 $ 0.23 $ (2.03 ) Diluted income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.04 $ 0.08 $ 0.22 $ (1.03 ) Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax — — 0.01 (1.00 ) Diluted income (loss) per share attributable to The AES Corporation $ 0.04 $ 0.08 $ 0.23 $ (2.03 ) Dividends declared per common share $ 0.12 $ — $ 0.12 $ 0.25 Quarter Ended 2016 Mar 31 June 30 Sept 30 Dec 31 Revenue $ 2,530 $ 2,452 $ 2,639 $ 2,660 Operating margin 501 556 691 632 Income (loss) from continuing operations, net of tax (2) 87 2 238 (136 ) Loss from discontinued operations, net of tax (13 ) (389 ) (9 ) (557 ) Net income (loss) $ 74 $ (387 ) $ 229 $ (693 ) Net income (loss) attributable to The AES Corporation $ 126 $ (482 ) $ 175 $ (949 ) Basic income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.21 $ (0.15 ) $ 0.26 $ (0.35 ) Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax (0.02 ) (0.58 ) — (1.09 ) Basic income (loss) per share attributable to The AES Corporation $ 0.19 $ (0.73 ) $ 0.26 $ (1.44 ) Diluted income (loss) per share: Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax $ 0.20 $ (0.15 ) $ 0.26 $ (0.35 ) Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax (0.01 ) (0.58 ) — (1.09 ) Diluted income (loss) per share attributable to The AES Corporation $ 0.19 $ (0.73 ) $ 0.26 $ (1.44 ) Dividends declared per common share $ 0.11 $ — $ 0.11 $ 0.23 _____________________________ (1) Includes pre-tax impairment expense of $168 million , $90 million , $2 million and $277 million , for the first, second, third and fourth quarters of 2017 , respectively. See Note 19 — Asset Impairment Expense for further discussion. (2) Includes pre-tax impairment expense of $159 million , $235 million , $79 million and $623 million , for the first, second, third and fourth quarters of 2016 , respectively. See Note 19 — Asset Impairment Expense for further discussion.

Schedule I - Condensed Financ70

Schedule I - Condensed Financial Information of Parent (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Details [Line Items]
Schedule of Recourse Debt Detail	The following table summarizes the carrying amount and terms of recourse debt of the Company as of the periods indicated (in millions): Interest Rate Final Maturity December 31, 2017 December 31, 2016 Senior Unsecured Note LIBOR + 3.00% 2019 $ — $ 240 Senior Unsecured Note 8.00% 2020 228 469 Senior Unsecured Note 7.38% 2021 690 966 Drawings on secured credit facility LIBOR + 2.00% 2021 207 — Senior Secured Term Loan LIBOR + 2.00% 2022 521 — Senior Unsecured Note 4.88% 2023 713 713 Senior Unsecured Note 5.50% 2024 738 738 Senior Unsecured Note 5.50% 2025 573 573 Senior Unsecured Note 6.00% 2026 500 500 Senior Unsecured Note 5.13% 2027 500 — Term Convertible Trust Securities 6.75% 2029 — 517 Unamortized (discount) premium & debt issuance (costs), net (40 ) (45 ) Subtotal $ 4,630 $ 4,671 Less: Current maturities (5 ) — Noncurrent maturities $ 4,625 $ 4,671 December 31, Interest Rate Maturity 2017 2016 Senior Unsecured Note LIBOR + 3.00% 2019 $ — $ 240 Senior Unsecured Note 8.00% 2020 228 469 Senior Unsecured Note 7.38% 2021 690 966 Drawings on secured credit facility LIBOR + 2.00% 2021 207 — Senior Secured Term Loan LIBOR + 2.00% 2022 521 — Senior Unsecured Note 4.88% 2023 713 713 Senior Unsecured Note 5.50% 2024 738 738 Senior Unsecured Note 5.50% 2025 573 573 Senior Unsecured Note 6.00% 2026 500 500 Senior Unsecured Note 5.13% 2027 500 — Unamortized (discounts)/premiums & debt issuance (costs) (40 ) (45 ) Subtotal $ 4,630 $ 4,154 Less: Current maturities (5 ) — Total $ 4,625 $ 4,154
Junior Subordinated Notes Payable	December 31, Interest Rate Maturity 2017 2016 Term Convertible Trust Securities 6.75% 2029 $ — $ 517
Future Maturities of Debt	The following table summarizes the principal amounts due under our recourse debt for the next five years and thereafter (in millions): December 31, Net Principal Amounts Due 2018 $ 5 2019 5 2020 234 2021 902 2022 500 Thereafter 3,024 Unamortized (discount) premium & debt issuance (costs), net (40 ) Total recourse debt $ 4,630 As of December 31, 2017 scheduled maturities are presented in the following table (in millions): December 31, Annual Maturities 2018 $ 5 2019 5 2020 234 2021 902 2022 500 Thereafter 3,024 Unamortized (discount)/premium & debt issuance (costs) (40 ) Total debt $ 4,630

Schedule II - Valuation and Q71

Schedule II - Valuation and Qualifying Accounts Schedule of Valuation and Qualifying Accounts (Tables)	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
schedule of valuation and qualifying accounts [Table Text Block]	(in millions) Balance at Beginning of the Period Charged to Cost and Expense Amounts Written off Translation Adjustment Balance at End of the Period Allowance for accounts receivables (current and noncurrent)

General and Summary of Signif72

General and Summary of Significant Accounting Policies (Finite Lived Intangible Assets) (Details)	12 Months Ended
	Dec. 31, 2017
Minimum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years
Maximum
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	50 years

General and Summary of Signif73

General and Summary of Significant Accounting Policies New Accounting Pronouncements Adopted (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other Comprehensive Income (Loss), Effect of Change in Accounting Principle, Net of Taxes	$ 919	$ 1,036	$ (933)
Retained Earnings [Member] | Accounting Standard Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets		31
Retained Earnings [Member] | Accounting Standard Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	60
Other Noncurrent Assets [Member] | Accounting Standard Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	1,360
Deferred Income Tax Charge [Member] | Accounting Standard Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets		31
AOCI Attributable to Parent [Member] | Accounting Standard Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	20
Noncontrolling Interest [Member] | Accounting Standard Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	80
Service Concession Asset [Member] | Accounting Standard Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets		(1,360)
Inc (Dec) in Cash provided by Operating Actitvities [Domain] | Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	5	5	(5)
Dec (Inc) In Net Cash Used by Investing Activities [Domain] | Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	$ 135	$ (10)	$ 230

Inventory (Details)

Inventory (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Fuel and other raw materials	$ 284	$ 302
Spare parts and supplies	278	320
Total	$ 562	$ 622

Property, Plant and Equipment75

Property, Plant and Equipment (Components of PP&E) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	$ 24,119	$ 24,911
Accumulated depreciation	(7,942)	(7,919)
Property, Plant and Equipment, Net	16,177	16,992
Property Plant And Equipment Net Of Accumulated Depreciation Mortgaged Pledged Or Subject To Liens	10,000	10,000
Electric generation and distribution facilities
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	$ 21,529	22,337
Electric generation and distribution facilities | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	8 years
Electric generation and distribution facilities | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	40 years
Other buildings
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	$ 1,971	1,906
Other buildings | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Other buildings | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	71 years
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	$ 284	303
Furniture and Fixtures [Member] | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	2 years
Furniture and Fixtures [Member] | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	32 years
Other
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	$ 335	$ 365
Other | Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Other | Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Life	44 years

Property, Plant and Equipment76

Property, Plant and Equipment (Depreciation Expense, Software Amortization and Capitalized Interest) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 1,005	$ 1,002	$ 958
Interest capitalized during development and construction	139	118	$ 84
Property plant and equipment, net of accumulated depreciation mortgaged, pledged or subject to liens	$ 10,000	$ 10,000

Property, Plant and Equipment77

Property, Plant and Equipment (Regulated and Non-Regulated Generation and Distribution PP&E) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	$ 24,119	$ 24,911
Accumulated depreciation	(7,942)	(7,919)
Net electric generation and distribution assets and other	16,177	16,992
Regulated Operation [Member]
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	8,093	7,815
Accumulated depreciation	(3,357)	(3,299)
Net electric generation and distribution assets and other	4,736	4,516
Unregulated Operation [Member]
Property, Plant and Equipment [Line Items]
Electric generation, distribution assets and other	16,026	17,096
Accumulated depreciation	(4,585)	(4,620)
Net electric generation and distribution assets and other	$ 11,441	$ 12,476

Property, Plant and Equipment78

Property, Plant and Equipment (Asset Retirement Obligations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	$ 357	$ 247
Additional liabilities incurred	1	12
Asset Retirement Obligation, Other [Line Items]	(10)	1
Liabilities settled	(21)	(4)
Accretion expense	16	15
Change in estimated cash flows	25	86
Ending balance	$ 368	$ 357

Fair Value (Recurring Measureme

Fair Value (Recurring Measurements) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proceeds from Sale of Available-for-sale Securities	$ 1,398	$ 1,726	$ 1,226
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	780	914
Other than Temporary Impairment Losses, Investments	0
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	315	424
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	20	16
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	515	636
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	163	243
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	245	262
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	152	181
Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	412	522
Available-for-sale Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Available-for-sale Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	412	522
Available-for-sale Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	348	376
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	315	424
Derivative [Member] | Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	20	42
Derivative [Member] | Interest rate derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	262	300
Derivative [Member] | Cross-currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	3	18
Derivative [Member] | Foreign currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	30	64
Derivative [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Derivative [Member] | Level 1 | Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Derivative [Member] | Level 1 | Interest rate derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Derivative [Member] | Level 1 | Cross-currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Derivative [Member] | Level 1 | Foreign currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Derivative [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	103	114
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	163	243
Derivative [Member] | Level 2 | Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	19	40
Derivative [Member] | Level 2 | Interest rate derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	111	121
Derivative [Member] | Level 2 | Cross-currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	3	18
Derivative [Member] | Level 2 | Foreign currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	30	64
Derivative [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	245	262
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	152	181
Derivative [Member] | Level 3 | Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	1	2
Derivative [Member] | Level 3 | Interest rate derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	151	179
Derivative [Member] | Level 3 | Cross-currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Derivative [Member] | Level 3 | Foreign currency derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	0	0
Other debt securities | Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	207	205
Other debt securities | Available-for-sale Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Other debt securities | Available-for-sale Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	207	205
Other debt securities | Available-for-sale Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Commodity Contract [Member] | Derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	35	45
Commodity Contract [Member] | Derivative [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Commodity Contract [Member] | Derivative [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	30	38
Commodity Contract [Member] | Derivative [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	5	7
Certificates of Deposit [Member] | Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	153	260
Certificates of Deposit [Member] | Available-for-sale Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Certificates of Deposit [Member] | Available-for-sale Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	153	260
Certificates of Deposit [Member] | Available-for-sale Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Government debt securities [Domain] | Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	9
Government debt securities [Domain] | Available-for-sale Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Government debt securities [Domain] | Available-for-sale Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	9
Government debt securities [Domain] | Available-for-sale Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Debt securities | Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	360	474
Debt securities | Available-for-sale Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Debt securities | Available-for-sale Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	360	474
Debt securities | Available-for-sale Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Equity Funds [Member] | Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	52	48
Equity Funds [Member] | Available-for-sale Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Equity Funds [Member] | Available-for-sale Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	52	48
Equity Funds [Member] | Available-for-sale Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Equity Funds [Member] | Trading Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	20	16
Equity Funds [Member] | Trading Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	20	16
Equity Funds [Member] | Trading Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Equity Funds [Member] | Trading Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Equity securities | Available-for-sale Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	52	48
Equity securities | Available-for-sale Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Equity securities | Available-for-sale Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	52	48
Equity securities | Available-for-sale Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Foreign currency derivatives | Derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	269	309
Foreign currency derivatives | Derivative [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Foreign currency derivatives | Derivative [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	29	54
Foreign currency derivatives | Derivative [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	240	255
Cross-currency derivatives | Derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	29	4
Cross-currency derivatives | Derivative [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Cross-currency derivatives | Derivative [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	29	4
Cross-currency derivatives | Derivative [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Interest rate derivatives | Derivative [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	15	18
Interest rate derivatives | Derivative [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	0	0
Interest rate derivatives | Derivative [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	15	18
Interest rate derivatives | Derivative [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 0	$ 0

Fair Value (Level 3 Reconciliat

Fair Value (Level 3 Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	$ 21	$ 33
Included in regulatory liabilities	10	11
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	(12)	39
Fair Value, Net Derivative Liability Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	(4)	(32)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		133
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers out of Level 3	20
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	93	81	$ (24)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Period Increase (Decrease)	(7)	24
Commodity Contract [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	1	2
Included in regulatory liabilities	10	11
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	(12)	(11)
Fair Value, Net Derivative Liability Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers out of Level 3	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	4	5	3
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Period Increase (Decrease)	1	2
Foreign Exchange Contract [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	21	31
Included in regulatory liabilities	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	(36)	(22)
Fair Value, Net Derivative Liability Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		(15)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers out of Level 3	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	240	255	277
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Period Increase (Decrease)	(15)	16
Interest Rate Contract
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings	(1)	0
Included in regulatory liabilities	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements	36	72
Fair Value, Net Derivative Liability Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	(4)	(32)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		118
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers out of Level 3	20
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	(151)	(179)	$ (304)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Period Increase (Decrease)	7	6
Other comprehensive income - Derivative activity [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)	(23)	(30)
Other comprehensive income - Derivative activity [Member] | Commodity Contract [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	0
Other comprehensive income - Derivative activity [Member] | Foreign Exchange Contract [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	6
Other comprehensive income - Derivative activity [Member] | Interest Rate Contract
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)	$ (23)	(36)
Other Comprehensive Income- Foreign currency translation activity [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)		(49)
Other Comprehensive Income- Foreign currency translation activity [Member] | Commodity Contract [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)		0
Other Comprehensive Income- Foreign currency translation activity [Member] | Foreign Exchange Contract [Member]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)		(52)
Other Comprehensive Income- Foreign currency translation activity [Member] | Interest Rate Contract
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss)		$ 3

Fair Value (Quantitative Inform

Fair Value (Quantitative Information) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Fair Value Inputs Quantitative Information [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	$ 93	$ 81	$ (24)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Assets Liabilities Value	93
Foreign Exchange Contract [Member]
Fair Value Inputs Quantitative Information [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	240	255	277
Interest Rate Contract
Fair Value Inputs Quantitative Information [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	$ (151)	(179)	(304)
Interest Rate Contract | Minimum
Fair Value Inputs Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	1.90%
Interest Rate Contract | Maximum
Fair Value Inputs Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	5.10%
Interest Rate Contract | Weighted Average
Fair Value Inputs Quantitative Information [Line Items]
Fair Value Inputs, Entity Credit Risk	4.90%
Commodity Contract [Member]
Fair Value Inputs Quantitative Information [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	$ 4	$ 5	$ 3
Argentina, Pesos | Foreign Exchange Contract [Member]
Fair Value Inputs Quantitative Information [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	$ 240
Argentina, Pesos | Foreign Exchange Contract [Member] | Minimum
Fair Value Inputs Quantitative Information [Line Items]
Derivative, Forward Exchange Rate	0.228
Argentina, Pesos | Foreign Exchange Contract [Member] | Maximum
Fair Value Inputs Quantitative Information [Line Items]
Derivative, Forward Exchange Rate	0.523
Argentina, Pesos | Foreign Exchange Contract [Member] | Weighted Average
Fair Value Inputs Quantitative Information [Line Items]
Derivative, Forward Exchange Rate	0.366

Fair Value (Nonrecurring Measur

Fair Value (Nonrecurring Measurements) (Details) - USD ($)

2 Months Ended

3 Months Ended

6 Months Ended

8 Months Ended

12 Months Ended

Feb. 28, 2017

Dec. 31, 2017

Sep. 30, 2017

Jun. 30, 2017

Mar. 31, 2017

Dec. 31, 2016

Sep. 30, 2016

Jun. 30, 2016

Mar. 31, 2016

Dec. 31, 2015

Jun. 30, 2017

Jun. 30, 2016

Aug. 31, 2016

Dec. 31, 2017

Dec. 31, 2016

Dec. 31, 2015

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Other Asset Impairment Charges

$ 537,000,000

$ 1,096,000,000

$ 285,000,000

Goodwill impairment expense

0

0

317,000,000

Other non-operating expense

0

Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax

(611,000,000)

(1,385,000,000)

0

Impairment Expense Pre Tax Total

$ 277,000,000

$ 2,000,000

$ 90,000,000

$ 168,000,000

$ 623,000,000

$ 79,000,000

$ 235,000,000

$ 159,000,000

DPL Subsidiary

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Goodwill impairment expense

$ 317,000,000

Sul Subsidiary [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax

$ 602,000,000

Estimate of Fair Value Measurement [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

64,000,000

64,000,000

Long Lived Assets Held And Used [Member] | DPL Peaking Generation [Domain]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

2,000,000

5,000,000

5,000,000

2,000,000

Long Lived Assets Held And Used [Member] | Laurel Mountain [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

33,000,000

33,000,000

Other Asset Impairment Charges

[1]

121,000,000

Long Lived Assets Held And Used [Member] | Kilroot [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

20,000,000

$ 70,000,000

20,000,000

$ 70,000,000

Other Asset Impairment Charges

[1]

37,000,000

Long Lived Assets Held And Used [Member] | DPL Subsidiary

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Other Asset Impairment Charges

[1]

$ 66,000,000

235,000,000

624,000,000

Long Lived Assets Held And Used [Member] | Buffalo Gap [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

36,000,000

36,000,000

Other Asset Impairment Charges

[1]

$ 77,000,000

Long Lived Assets Held And Used [Member] | Other Subsidiaries [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Other Asset Impairment Charges

18,000,000

Long Lived Assets Held And Used [Member] | buffalo gap II [Member] [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

92,000,000

92,000,000

Other Asset Impairment Charges

[1]

159,000,000

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Laurel Mountain [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Laurel Mountain [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Laurel Mountain [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

33,000,000

33,000,000

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Kilroot [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Kilroot [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Kilroot [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

20,000,000

20,000,000

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | DPL Subsidiary | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

0

0

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | DPL Subsidiary | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

60,000,000

0

0

60,000,000

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | DPL Subsidiary | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

11,000,000

103,000,000

89,000,000

89,000,000

103,000,000

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Buffalo Gap [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Buffalo Gap [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Buffalo Gap [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

36,000,000

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Other Subsidiaries [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Other Subsidiaries [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | Other Subsidiaries [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | buffalo gap II [Member] [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | buffalo gap II [Member] [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

Long Lived Assets Held And Used [Member] | Estimate of Fair Value Measurement [Member] | buffalo gap II [Member] [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

92,000,000

Long Lived Assets Held And Used [Member] | Reported Value Measurement [Member] | Laurel Mountain [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1],[2]

154,000,000

154,000,000

Long Lived Assets Held And Used [Member] | Reported Value Measurement [Member] | Kilroot [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1],[2]

69,000,000

69,000,000

Long Lived Assets Held And Used [Member] | Reported Value Measurement [Member] | DPL Subsidiary

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1],[2]

$ 77,000,000

$ 787,000,000

324,000,000

324,000,000

$ 787,000,000

Long Lived Assets Held And Used [Member] | Reported Value Measurement [Member] | Buffalo Gap [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1],[2]

$ 113,000,000

Long Lived Assets Held And Used [Member] | Reported Value Measurement [Member] | Other Subsidiaries [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

18,000,000

18,000,000

Long Lived Assets Held And Used [Member] | Reported Value Measurement [Member] | buffalo gap II [Member] [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1],[2]

$ 251,000,000

Long Lived Assets Held For Sale [Member] | DPL Peaking Generation [Domain]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Other Asset Impairment Charges

[1]

109,000,000

Long Lived Assets Held For Sale [Member] | Kazakhstan [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Other Asset Impairment Charges

94,000,000

Long Lived Assets Held For Sale [Member] | Kazakhstan Hydro [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Other Asset Impairment Charges

$ 92,000,000

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | DPL Peaking Generation [Domain] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

0

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | DPL Peaking Generation [Domain] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

237,000,000

237,000,000

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | DPL Peaking Generation [Domain] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1]

0

0

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Kazakhstan [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Kazakhstan [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

29,000,000

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Kazakhstan [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Kazakhstan Hydro [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

0

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Kazakhstan Hydro [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

92,000,000

92,000,000

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Kazakhstan Hydro [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

0

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Sul Subsidiary [Member] | Level 1

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

0

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Sul Subsidiary [Member] | Level 2

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

470,000,000

470,000,000

Long Lived Assets Held For Sale [Member] | Estimate of Fair Value Measurement [Member] | Sul Subsidiary [Member] | Level 3

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

0

0

Long Lived Assets Held For Sale [Member] | Reported Value Measurement [Member] | DPL Peaking Generation [Domain]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

[1],[2]

$ 346,000,000

$ 346,000,000

Long Lived Assets Held For Sale [Member] | Reported Value Measurement [Member] | Kazakhstan [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

$ 171,000,000

Long Lived Assets Held For Sale [Member] | Reported Value Measurement [Member] | Kazakhstan Hydro [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

$ 190,000,000

190,000,000

Long Lived Assets Held For Sale [Member] | Reported Value Measurement [Member] | Sul Subsidiary [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Assets, Fair Value Disclosure, Nonrecurring

$ 1,581,000,000

$ 1,581,000,000

Discontinued Operations, Held-for-sale [Member] | Sul Subsidiary [Member]

Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]

Other Asset Impairment Charges

[1]

$ 783,000,000

[1]

See Note 19—Asset Impairment Expense for further information.

[2]

Represents the carrying values at the dates of measurement, before fair value adjustment.

Fair Value (Nonrecurring Unobse

Fair Value (Nonrecurring Unobservable Inputs) (Details) - USD ($)		12 Months Ended
		Dec. 31, 2017	Feb. 28, 2017	Dec. 31, 2016	Aug. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Fair Value | Level 3
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		$ 64,000,000
Long Lived Assets Held And Used [Member] | Laurel Mountain [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		33,000,000
Long Lived Assets Held And Used [Member] | Buffalo Gap [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring				$ 36,000,000
Long Lived Assets Held And Used [Member] | buffalo gap II [Member] [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring				92,000,000
Long Lived Assets Held And Used [Member] | Kilroot [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		20,000,000						$ 70,000,000
Long Lived Assets Held And Used [Member] | Fair Value | Level 3 | Laurel Mountain [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	[1]	33,000,000
Long Lived Assets Held And Used [Member] | Fair Value | Level 3 | Buffalo Gap [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	[1]				$ 36,000,000
Long Lived Assets Held And Used [Member] | Fair Value | Level 3 | DPL Subsidiary
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	[1]		$ 11,000,000	$ 103,000,000		$ 89,000,000
Long Lived Assets Held And Used [Member] | Fair Value | Level 3 | buffalo gap II [Member] [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	[1]						$ 92,000,000
Long Lived Assets Held And Used [Member] | Fair Value | Level 3 | Kilroot [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	[1]	$ 20,000,000
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Minimum | Laurel Mountain [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(30.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(61.00%)
Fair Value Inputs, Discount Rate		0.00%
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Minimum | buffalo gap II [Member] [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(0.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(0.00%)
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Minimum | Kilroot [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(85.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(31.80%)
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Maximum | Laurel Mountain [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(2.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(73.00%)
Fair Value Inputs, Discount Rate		0.00%
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Maximum | buffalo gap II [Member] [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(0.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(0.00%)
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Maximum | Kilroot [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(17.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(28.00%)
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Weighted Average | Laurel Mountain [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(0.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(64.00%)
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Weighted Average | DPL Subsidiary
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Discount Rate		7.00%
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Weighted Average | buffalo gap II [Member] [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(0.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(0.00%)
Fair Value Inputs, Discount Rate		0.00%
Income Approach Valuation Technique [Member] | Long Lived Assets Held And Used [Member] | Weighted Average | Kilroot [Member]
Fair Value Assets Measured On Nonrecurring Basis Unobservable Inputs [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate		(16.00%)
Fair Value Inputs, Long-term Pre-tax Operating Margin, Percent		(6.00%)
Fair Value Inputs, Discount Rate		8.00%
[1]	See Note 19—Asset Impairment Expense for further information.

Fair Value (Instruments Not Mea

Fair Value (Instruments Not Measured at Fair Value) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
ASSETS
Non-Recourse Debt		$ 15,340	$ 14,783
Liabilities [Abstract]
Recourse debt		4,630	4,671
Carrying Amount
ASSETS
Accounts receivable - noncurrent	[1]	163	232
Non-Recourse Debt		15,340	14,783
Liabilities [Abstract]
Recourse debt		4,630	4,671
Fair Value
ASSETS
Accounts receivable - noncurrent	[1]	217	342
Non-Recourse Debt		15,890	15,185
Liabilities [Abstract]
Recourse debt		4,920	4,899
Value added tax		31	24
Fair Value | Level 1
ASSETS
Accounts receivable - noncurrent	[1]	0	0
Non-Recourse Debt		0	0
Liabilities [Abstract]
Recourse debt		0	0
Fair Value | Level 2
ASSETS
Accounts receivable - noncurrent	[1]	6	20
Non-Recourse Debt		13,350	14,140
Liabilities [Abstract]
Recourse debt		4,920	4,899
Fair Value | Level 3
ASSETS
Accounts receivable - noncurrent	[1]	211	322
Non-Recourse Debt		2,540	1,045
Liabilities [Abstract]
Recourse debt		$ 0	$ 0
[1]	These amounts primarily relate to amounts due from CAMMESA, the administrator of the wholesale electricity market in Argentina, and are included in Other noncurrent assets in the accompanying Consolidated Balance Sheets. The fair value and carrying amount of these receivables exclude VAT of $31 million and $24 million as of December 31, 2017 and 2016, respectively.

Investments In Marketable Secur

Investments In Marketable Securities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Investments, Debt and Equity Securities [Abstract]
Other than Temporary Impairment Losses, Investments	$ 0

Derivative Instruments and He86

Derivative Instruments and Hedging Activities (Outstanding Derivative Notionals and Terms by Type) (Details) $ in Millions	Dec. 31, 2017USD ($)
Derivative [Line Items]
Derivative, notional amount	$ 3,600
Libor and Euribor [Member] | Interest Rate Contract
Derivative [Line Items]
Derivative, notional amount	4,481
Argentina, Pesos | Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative, notional amount	187
Chilean Peso CLP [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative, notional amount	410
Colombian Peso COP [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative, notional amount	305
Other unspecified currency [Domain] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative, notional amount	303
Unidad de Fomento (funds code) | Cross Currency Interest Rate Contract [Member]
Derivative [Line Items]
Derivative, notional amount	$ 410

Derivative Instruments and He87

Derivative Instruments and Hedging Activities (Foreign Currency Derivatives) (Details) $ in Billions	Dec. 31, 2017USD ($)
Derivative [Line Items]
Derivative, notional amount	$ 3.6

Derivative Instruments and He88

Derivative Instruments and Hedging Activities (Assets and LIabilities - Designated vs. Not Designated Hedging Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Total asset derivatives	$ 348	$ 376
Total liability derivatives	315	424
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	57	51
Total liability derivatives	138	358
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	291	325
Total liability derivatives	177	66
Interest Rate Contract
Derivatives, Fair Value [Line Items]
Total asset derivatives	15	18
Total liability derivatives	262	300
Interest Rate Contract | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	15	18
Total liability derivatives	125	295
Interest Rate Contract | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	0	0
Total liability derivatives	137	5
Cross Currency Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Total asset derivatives	29	4
Total liability derivatives	3	18
Cross Currency Interest Rate Contract [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	29	4
Total liability derivatives	3	18
Cross Currency Interest Rate Contract [Member] | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	0	0
Total liability derivatives	0	0
Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Total asset derivatives	269	309
Total liability derivatives	30	64
Foreign Exchange Contract [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	8	9
Total liability derivatives	1	19
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	261	300
Total liability derivatives	29	45
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Total asset derivatives	35	45
Total liability derivatives	20	42
Commodity Contract [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	5	20
Total liability derivatives	9	26
Commodity Contract [Member] | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	30	25
Total liability derivatives	$ 11	$ 16

Derivative Instruments and He89

Derivative Instruments and Hedging Activities (Assets and Liabilities - Current vs. Noncurrent Derivative instruments) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative Asset, Current		$ 84	$ 99
Derivative Liability, Current		211	155
Derivative Asset, Noncurrent		264	277
Derivative Liability, Noncurrent		104	269
Total asset derivatives		348	376
Total liability derivatives		315	424
Contracts Subject To Netting Arrangements
Derivatives, Fair Value [Line Items]
Total liability derivatives	[1]	15	41
Collateral Already Posted, Aggregate Fair Value	[1]	$ 9	$ 18
[1]	Based on the credit rating of certain subsidiaries

Derivative Instruments and He90

Derivative Instruments and Hedging Activities Derivative Instruments and Hedging Activities (Effective Portion of Cash Flow Hedges) (Details) - Cash Flow Hedging - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Losses) Recognized in AOCL, Effective Portion		$ (22)	$ 12	$ (73)
Gains (Losses) Reclassified from AOCL into Earnings, Effective Portion		(51)	(45)	(77)
Gain (Loss) on Derivative Instruments, Net, Pretax		15	3	182
AOCI before tax expected increase (decrease) next 12 months		(58)
Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Losses) Recognized in AOCL, Effective Portion		(66)	(35)	(103)
Gains (Losses) Reclassified from AOCL into Earnings, Effective Portion		(82)	(101)	(116)
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net		3	(1)	(6)
Loss on discontinuation of cash flow hedge due to forecasted transaction probable of not occurring	[1]	(13)	0	0
Cross Currency Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Losses) Recognized in AOCL, Effective Portion		31	21	(20)
Gains (Losses) Reclassified from AOCL into Earnings, Effective Portion		34	8	(24)
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Losses) Recognized in AOCL, Effective Portion		(5)	(4)	10
Gains (Losses) Reclassified from AOCL into Earnings, Effective Portion		(20)	(8)	32
Gain (Loss) on Derivative Instruments, Net, Pretax		1	19	211
Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Losses) Recognized in AOCL, Effective Portion		18	30	40
Gains (Losses) Reclassified from AOCL into Earnings, Effective Portion		17	56	31
Gain (Loss) on Derivative Instruments, Net, Pretax		$ 14	$ (16)	$ (29)
[1]	Cash flow hedge was discontinued because it was probable the forecasted transaction will not occur.

Derivative Instruments and He91

Derivative Instruments and Hedging Activities Derivative Instruments and Hedging Activities (Ineffective Portion of Cash Flow Hedges) (Details) - Cash Flow Hedging - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ (51)	$ (45)	$ (77)
Accumulated Other Comprehensive Income Loss Before Tax Expected Increase Decrease Next Twelve Months	58
Interest Rate Contract
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(82)	(101)	(116)
Gain (Losses) Recognized in Earnings, Ineffective Portion	3	(1)	(6)
Foreign Exchange Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(20)	(8)	32
Cross Currency Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 34	$ 8	$ (24)

Financing Receivables (Details)

Financing Receivables (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)agreement	Dec. 31, 2016USD ($)
Schedule of Financing Receivables [Line Items]
Financing receivable	$ 194	$ 256
Number of Foninvemem Agreements | agreement	3
Foninvemem Agreement, collection period		10 years
ARGENTINA
Schedule of Financing Receivables [Line Items]
Financing receivable	$ 177	$ 236
Derivative Assets, Gross	240	255
Brazil
Schedule of Financing Receivables [Line Items]
Financing receivable	$ 17	$ 20

Investments In and Advances T93

Investments In and Advances To Affiliates - Effective Equity Ownership Interest and Carrying Values (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates		$ 1,197	$ 621	$ 610
sPower [Member]
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates		$ 508	$ 0
Equity Method Investment, Ownership Percentage		50.00%	0.00%
Gener Subsidiary [Member]
Investments in and Advances to Affiliates [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		67.00%
Barry
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates	[1]	$ 0	$ 0
Equity Method Investment, Ownership Percentage	[1]	100.00%	100.00%
Elsta
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates	[1]	$ 38	$ 41
Equity Method Investment, Ownership Percentage	[1]	50.00%	50.00%
Distributed Energy [Member]
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates	[1]	$ 15	$ 22
Equity Method Investment, Ownership Percentage	[1]	95.00%	95.00%
Guacolda Affiliate [Member]
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates	[2]	$ 357	$ 362
Equity Method Investment, Ownership Percentage	[2]	33.00%	33.00%
OPGC
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates	[3]	$ 269	$ 195
Equity Method Investment, Ownership Percentage	[3]	49.00%	49.00%
Other Affiliates [Member]
Investments in and Advances to Affiliates [Line Items]
Investments in and advances to affiliates		$ 10	$ 1
Gener Subsidiary [Member] | Guacolda Affiliate [Member]
Investments in and Advances to Affiliates [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
[1]	Represent VIEs in which the Company holds a variable interest, but is not the primary beneficiary.
[2]	The Company's ownership in Guacolda is held through AES Gener, a 67%-owned consolidated subsidiary. AES Gener owns 50% of Guacolda, resulting in an AES effective ownership in Guacolda of 33%.
[3]	OPGC has one coal-fired project under development which is an expansion of our existing OPGC business. The project started construction in April 2014 and is expected to begin operations in 2019.

Investments In and Advances T94

Investments In and Advances To Affiliates - Summary of Financial Information of Affiliates & Subsidiaries (Details) - USD ($) $ in Millions		Nov. 15, 2017	Jul. 25, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investments in and Advances to Affiliates [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax				$ (1,876)	$ (2,756)	$ (3,883)
Investments in and advances to affiliates				1,197	621	610
Gain (Loss) on Disposition of Business				(52)	29	29
Payments to Acquire Businesses and Interest in Affiliates				625	55	17
Proceeds from the sale of businesses, net of cash sold, and equity method investments				108	631	138
Net equity in earnings of affiliates				$ 71	$ 36	105
Barry
Investments in and Advances to Affiliates [Line Items]
Equity Method Investment, Ownership Percentage	[1]			100.00%	100.00%
Investments in and advances to affiliates	[1]			$ 0	$ 0
Long Term Liabilities Associated With Debt Agreement Resulting In Loss Of Control				$ 45	$ 41
Elsta
Investments in and Advances to Affiliates [Line Items]
Equity Method Investment, Ownership Percentage	[1]			50.00%	50.00%
Investments in and advances to affiliates	[1]			$ 38	$ 41
sPower [Member]
Investments in and Advances to Affiliates [Line Items]
Equity Method Investment, Ownership Percentage		2.00%	48.00%
Payments to Acquire Businesses, Net of Cash Acquired		$ 19	$ 461
guacolda [Member]
Investments in and Advances to Affiliates [Line Items]
Net equity in earnings of affiliates						66
Parent [Member] | guacolda [Member]
Investments in and Advances to Affiliates [Line Items]
Net equity in earnings of affiliates						$ 46
[1]	Represent VIEs in which the Company holds a variable interest, but is not the primary beneficiary.

Investments In and Advances T95

Investments In and Advances To Affiliates - Summarized Financial Information (Details) - USD ($) $ in Millions	Nov. 15, 2017	Jul. 25, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Revenue			$ 2,643	$ 2,693	$ 2,613	$ 2,581	$ 2,660	$ 2,639	$ 2,452	$ 2,530	$ 10,530	$ 10,281	$ 11,260
Operating margin			643	642	625	554	632	691	556	501	2,464	2,380	2,663
Net income (loss)			(1,286)	$ 261	$ 150	$ 98	(693)	$ 229	$ (387)	$ 74	(777)	(777)	762
Assets, Current			6,398				6,416				6,398	6,416
Liabilities, Current			6,028				5,277				6,028	5,277
Liabilities, Noncurrent			21,402				24,365				21,402	24,365
Stockholders' Equity Attributable to Noncontrolling Interest			2,380				2,906				2,380	2,906
Stockholders' Equity Attributable to Parent			2,465				2,794				2,465	2,794
Undistributed Earnings Of Minority Owned Affiliates Included In Retained Earnings			254								254
Distributions Received From Minority Owned Affiliates											69	24	18
Basis Difference Between Carrying Amount And Investment			46								46
Minority Owned Affiliates
Schedule of Equity Method Investments [Line Items]
Revenue											762	586	641
Operating margin											165	145	152
Net income (loss)											72	64	210
Assets, Current			418				308				418	308
Assets, Noncurrent			5,372				2,577				5,372	2,577
Liabilities, Current			633				626				633	626
Liabilities, Noncurrent			2,629				1,209				2,629	1,209
Stockholders' Equity Attributable to Parent			2,527				1,048				2,527	1,048
Majority Owned Affiliates
Schedule of Equity Method Investments [Line Items]
Revenue											16	23	24
Operating margin											5	9	11
Net income (loss)											(15)	(2)	$ 6
Assets, Current			70				16				70	16
Assets, Noncurrent			102				181				102	181
Liabilities, Current			10				10				10	10
Liabilities, Noncurrent			147				122				147	122
Stockholders' Equity Attributable to Parent			$ 15				$ 65				$ 15	$ 65
sPower [Member]
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	$ 19	$ 461

Total Other Non-Operating Expen

Total Other Non-Operating Expense (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Schedule of Other Nonoperating Income (Expense) [Line Items]
Other Nonoperating Expense	$ 0

Goodwill and Other Intangible97

Goodwill and Other Intangible Assets (Goodwill Roll Forward) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Goodwill	$ 3,814	$ 3,912
Accumulated impairment losses	(2,755)	(2,755)
Net balance	1,059	1,157
Goodwill impairment expense	0	0	$ (317)
Goodwill, Transfers	(98)
US
Goodwill [Roll Forward]
Goodwill	2,674	2,674
Accumulated impairment losses	(2,633)	(2,633)
Net balance	41	41
Goodwill, Transfers	0
Andes
Goodwill [Roll Forward]
Goodwill	869	899
Accumulated impairment losses	0	0
Net balance	869	899
Goodwill, Transfers	(30)
MCAC
Goodwill [Roll Forward]
Goodwill	149	149
Accumulated impairment losses	0	0
Net balance	149	149
Goodwill, Acquired During Period	0
Eurasia
Goodwill [Roll Forward]
Goodwill	122	190
Accumulated impairment losses	(122)	(122)
Net balance	0	$ 68
Goodwill, Transfers	$ (68)

Goodwill and Other Intangible98

Goodwill and Other Intangible Assets (Intangible Assets) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets, Net [Abstract]
Gross Balance		$ 728	$ 612
Accumulated Amortization		(441)	(399)
Net Balance		287	213
Indefinite-Lived Intangible Assets (Excluding Goodwill)		79	74
Indefinite- lived intangible assets, Amortization		0	0
Intangible Assets, Gross		807	686
Intangible Assets, Net		366	287
Land Use Rights [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Indefinite-Lived Intangible Assets (Excluding Goodwill)		45	47
Indefinite- lived intangible assets, Amortization		0	0
Water rights
Finite-Lived Intangible Assets, Net [Abstract]
Indefinite-Lived Intangible Assets (Excluding Goodwill)		20	17
Indefinite- lived intangible assets, Amortization		0	0
Other
Finite-Lived Intangible Assets, Net [Abstract]
Indefinite-Lived Intangible Assets (Excluding Goodwill)		14	10
Indefinite- lived intangible assets, Amortization		0	0
Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Gross Balance		416	396
Accumulated Amortization		(330)	(304)
Net Balance		86	92
Contractual payment rights
Finite-Lived Intangible Assets, Net [Abstract]
Gross Balance	[1]	65	56
Accumulated Amortization	[1]	(47)	(42)
Net Balance	[1]	18	14
Project Development Rights [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Gross Balance		57	4
Accumulated Amortization		(1)	(1)
Net Balance		56	3
Contracts
Finite-Lived Intangible Assets, Net [Abstract]
Gross Balance		92	53
Accumulated Amortization		(21)	(15)
Net Balance		71	38
Other
Finite-Lived Intangible Assets, Net [Abstract]
Gross Balance	[2]	98	103
Accumulated Amortization	[2]	(42)	(37)
Net Balance	[2]	$ 56	$ 66
[1]	Represent legal rights to receive system reliability payments from the regulator.
[2]	Includes management rights, sales concessions, gas extraction rights, and other individually insignificant intangible assets.

Goodwill and Other Intangible99

Goodwill and Other Intangible Assets (Intangible Assets Acquired) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Indefinite-lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 112	$ 70
Project Development Rights [Member]
Indefinite-lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 53
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	30 years
Other Intangible Assets [Member]
Indefinite-lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired		$ 5
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		13 years
Other intangible assets acquired	$ 8
Contracts
Indefinite-lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 34	$ 24
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	25 years	26 years
Computer Software, Intangible Asset [Member]
Indefinite-lived Intangible Assets [Line Items]
Finite-lived Intangible Assets Acquired	$ 17	$ 41
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years	4 years

Goodwill and Other Intangibl100

Goodwill and Other Intangible Assets (Expected Amortization Expense) (Details) $ in Millions	Dec. 31, 2017USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,016	$ 33
2,017	31
2,018	27
2,019	23
2,020	23
Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,016	17
2,017	14
2,018	12
2,019	10
2,020	9
Contracts
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,016	5
2,017	5
2,018	5
2,019	5
2,020	5
Other
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,016	11
2,017	12
2,018	10
2,019	8
2,020	$ 9

Goodwill and Other Intangibl101

Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Feb. 18, 2015
Goodwill [Line Items]
Goodwill impairment expense		$ 0	$ 0	$ 317
Goodwill		1,059	1,157
Goodwill		3,814	$ 3,912
Main street power [Member]
Goodwill [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired					100.00%
DPL Subsidiary [Member]
Goodwill [Line Items]
Goodwill impairment expense	$ 317
Goodwill		$ 317

Goodwill and Other Intangibl102

Goodwill and Other Intangible Assets Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 34	$ 37	$ 47

Regulatory Assets and Liabil103

Regulatory Assets and Liabilities (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Current Regulatory Assets		$ 119	$ 88
Total Non Current Regulatory Assets		542	655
TOTAL REGULATORY ASSETS		661	743
Total Current Regulatory Liabilities		17	41
Total Non Current Regulatory Liabilities		1,079	802
TOTAL REGULATORY LIABILITIES		1,096	843
Efficiency Program Costs
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Current Regulatory Liabilities		10	14
Deferred Income Tax Charge [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Non Current Regulatory Liabilities		243	2
Asset Retirement Obligation Costs
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Non Current Regulatory Liabilities		830	795
Other Regulatory Liabilities
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Current Regulatory Liabilities		7	27
Total Non Current Regulatory Liabilities		6	5
El Salvador Tariff Recoveries
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Current Regulatory Assets		59	54
Pension Costs
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Non Current Regulatory Assets	[1]	298	316
Income Taxes Recoverable From Customers
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Non Current Regulatory Assets	[1]	0	87
Deferred Midwest Independent Service Operator Costs
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Non Current Regulatory Assets		102	114
Environmental Restoration Costs [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Non Current Regulatory Assets		48	41
Other Regulatory Assets
Schedule of Regulatory Assets and Liabilities [Line Items]
Total Current Regulatory Assets		60	34
Total Non Current Regulatory Assets		$ 94	$ 97
[1]	Past expenditures on which the Company earns a rate of return.

Regulatory Assets and Liabil104

Regulatory Assets and Liabilities Regulatory Assets and Liabilities - by Reportable Segment (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	$ 661	$ 743
Regulatory Liabilities	1,096	843
Brazil SBU
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	0	0
Regulatory Liabilities	1	1
US SBU
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	602	689
Regulatory Liabilities	1,095	842
MCAC SBU
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	59	54
Regulatory Liabilities	$ 0	$ 0

Debt (Non-Recourse Debt Carryin

Debt (Non-Recourse Debt Carrying Amounts and Terms) (Details) - USD ($)		Dec. 31, 2017	Jun. 30, 2017	Feb. 28, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net		$ (394,000,000)			$ (425,000,000)
Non-Recourse Debt		15,340,000,000			14,783,000,000
Non-recourse Debt Current Maturities		(2,164,000,000)			(1,052,000,000)
Non-recourse debt - noncurrent, balance at variable interest entities		13,176,000,000			13,731,000,000
Derivative, notional amount		$ 3,600,000,000
Interest rate swap, fixed minimum interest rate		2.49%
Interest rate swap, fixed maximum interest rate		8.00%
Variable Rate Debt | Bank loans
Debt Instrument [Line Items]
Weighted Average Interest Rate		4.52%
Variable Rate Debt | Notes and bonds
Debt Instrument [Line Items]
Weighted Average Interest Rate		8.06%
Variable Rate Debt | Debt to (or guaranteed by) multilateral, export credit agencies or development banks
Debt Instrument [Line Items]
Weighted Average Interest Rate	[1]	3.28%
Fixed Rate Debt | Bank loans
Debt Instrument [Line Items]
Weighted Average Interest Rate		4.54%
Fixed Rate Debt | Notes and bonds
Debt Instrument [Line Items]
Weighted Average Interest Rate		5.68%
Fixed Rate Debt | Debt to (or guaranteed by) multilateral, export credit agencies or development banks
Debt Instrument [Line Items]
Weighted Average Interest Rate	[1]	5.35%
Fixed Rate Debt | Other
Debt Instrument [Line Items]
Weighted Average Interest Rate		5.81%
Nonrecourse Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 3,508,000,000
Other | Fixed Rate Debt
Debt Instrument [Line Items]
Non-Recourse Debt		26,000,000			30,000,000
Debt to (or guaranteed by) multilateral, export credit agencies or development banks | Variable Rate Debt
Debt Instrument [Line Items]
Non-Recourse Debt	[1]	3,668,000,000			3,189,000,000
Debt to (or guaranteed by) multilateral, export credit agencies or development banks | Fixed Rate Debt
Debt Instrument [Line Items]
Non-Recourse Debt	[1]	271,000,000			328,000,000
Notes and bonds | Variable Rate Debt
Debt Instrument [Line Items]
Non-Recourse Debt		900,000,000			471,000,000
Notes and bonds | Fixed Rate Debt
Debt Instrument [Line Items]
Non-Recourse Debt		7,388,000,000			7,822,000,000
Bank loans | Variable Rate Debt
Debt Instrument [Line Items]
Non-Recourse Debt		2,488,000,000			2,601,000,000
Bank loans | Fixed Rate Debt
Debt Instrument [Line Items]
Non-Recourse Debt		993,000,000			$ 767,000,000
AES Argentina [Member] | Nonrecourse Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		310,000,000		$ 75,000,000
AES Argentina [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 300,000,000
AES Southland [Domain] | Nonrecourse Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 557,000,000	$ 1,967,000,000
Weighted Average Interest Rate			4.50%
AES Southland [Domain] | Senior Secured Note through 2040 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 1,500,000,000
AES Southland [Domain] | Senior Secured Term Loan through 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 492,000,000
[1]	(2)Multilateral loans include loans funded and guaranteed by bilaterals, multilaterals, development banks and other similar institutions.

Debt (Non-Recourse Debt Maturit

Debt (Non-Recourse Debt Maturity Schedule) (Details) - USD ($)	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Debt Details [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ (394,000,000)		$ (425,000,000)
Non Recourse Debt Total	15,340,000,000		$ 14,783,000,000
Nonrecourse Debt [Member]
Debt Details [Line Items]
Debt Instrument, Face Amount	3,508,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Two	796,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Three	1,396,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Four	1,833,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Five	1,768,000,000
Long-term Debt, Maturities, Repayments of Principal after Year Five	7,696,000,000
Nonrecourse Debt [Member]
Debt Details [Line Items]
Non-Recourse Debt	2,245,000,000
AES Southland [Domain] | Nonrecourse Debt [Member]
Debt Details [Line Items]
Debt Instrument, Face Amount	$ 557,000,000	$ 1,967,000,000

Debt (Subsidiary Non-Recourse D

Debt (Subsidiary Non-Recourse Debt in Default or Accelerated) (Details) $ in Millions	Dec. 31, 2017USD ($)
Debt Details [Line Items]
Debt default amount	$ 1,019
Alto Maipo [Member] | Covenant Violation
Debt Details [Line Items]
Non-Recourse Debt	618
PUERTO RICO | Covenant Violation
Debt Details [Line Items]
Debt default amount	365
Non-Recourse Debt	365
AES Ilumina [Member] | Covenant Violation
Debt Details [Line Items]
Non-Recourse Debt	36
Net Assets, Segment [Member] | Alto Maipo [Member]
Debt Details [Line Items]
Non-Recourse Debt	352
Net Assets, Segment [Member] | PUERTO RICO
Debt Details [Line Items]
Non-Recourse Debt	692
Net Assets, Segment [Member] | AES Ilumina [Member]
Debt Details [Line Items]
Non-Recourse Debt	$ 54

Debt (Non-recourse Debt Narrati

Debt (Non-recourse Debt Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2017	Feb. 28, 2017
Debt Instrument [Line Items]
Construction line of credit facility remaining borrowing capacity	$ 1,800,000,000
Other line of credit remaining borrowing capacity	1,700,000,000
Loss on extinguishment of debt	68,000,000	$ 13,000,000	$ 182,000,000
Restricted cash and debt service reserves	642,000,000	$ 535,000,000
Restricted net assets	2,800,000,000
Non-Recourse Debt
Debt Instrument [Line Items]
Debt face amount	3,508,000,000
Repayments of long-term debt	(2,550,000,000)
Loss on extinguishment of debt	23,000,000
Non-Recourse Debt | AES Tiete [Domain]
Debt Instrument [Line Items]
Debt face amount	585,000,000
Repayments of long-term debt	(293,000,000)
Loss on extinguishment of debt	(5,000,000)
Non-Recourse Debt | Gener Subsidiary [Member]
Debt Instrument [Line Items]
Debt face amount	335,000,000
Repayments of long-term debt	(426,000,000)
Loss on extinguishment of debt	(20,000,000)
Non-Recourse Debt | AES Argentina [Member]
Debt Instrument [Line Items]
Debt face amount	310,000,000				$ 75,000,000
Repayments of long-term debt	(181,000,000)
Loss on extinguishment of debt	65,000,000
Non-Recourse Debt | IPALCO Enterprises, Inc. [Member]
Debt Instrument [Line Items]
Debt face amount	608,000,000
Repayments of long-term debt	(528,000,000)
Loss on extinguishment of debt	(9,000,000)
Non-Recourse Debt | AES Southland [Domain]
Debt Instrument [Line Items]
Debt face amount	557,000,000			$ 1,967,000,000
Repayments of long-term debt	0
Loss on extinguishment of debt	0
Non-Recourse Debt | DPL Subsidiary
Debt Instrument [Line Items]
Debt face amount	103,000,000
Repayments of long-term debt	(249,000,000)
Loss on extinguishment of debt	(3,000,000)
Non-Recourse Debt | Masinloc Subsidiary [Member]
Debt Instrument [Line Items]
Debt face amount	160,000,000
Repayments of long-term debt	(51,000,000)
Loss on extinguishment of debt	0
Non-Recourse Debt | MCAC
Debt Instrument [Line Items]
Debt face amount	262,000,000
Repayments of long-term debt	0
Loss on extinguishment of debt	0
Non-Recourse Debt | Los Mina [Member]
Debt Instrument [Line Items]
Debt face amount	303,000,000
Repayments of long-term debt	(275,000,000)
Loss on extinguishment of debt	(4,000,000)
Non-Recourse Debt | Other Subsidiaries [Member]
Debt Instrument [Line Items]
Debt face amount	285,000,000
Repayments of long-term debt	(547,000,000)
Loss on extinguishment of debt	$ (1,000,000)

Debt (Recourse Debt Carrying Am

Debt (Recourse Debt Carrying Amount and Terms) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Recourse Debt Total	$ 4,630	$ 4,671
Recourse Debt Current	(5)	0
Recourse Debt Non Current	$ 4,625	$ 4,671
8.00% Senior Unsecured Note Due 2017 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		8.00%
Senior Unsecured Note LIBOR plus 3% due 2019 | Recourse Debt | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%	3.00%
8.00% Senior Unsecured Note Due 2020 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	8.00%	8.00%
7.375% Senior Notes Due 2021 [Member] [Member] | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	7.38%
Revolving Credit Facility [Member] | Recourse Debt | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%	2.00%
Senior Secured Term Loan due 2022 [Member] | Recourse Debt | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%	2.00%
4.88% Senior Unsecured Note Due 2023 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		4.88%
5.50% Senior Unsecured Note Due 2024 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		5.50%
5.50% Unsecured senior notes due 2025 [Domain] | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		5.50%
6.00% senior notes due 2026 [Domain] | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		6.00%
6.75% Term Convertible Trust Securities Due 2029 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	6.75%	6.75%
Recourse Debt Total	$ 0	$ 517
Unamortized (discount) premium & debt issuance (costs), net
Debt Instrument [Line Items]
Recourse Debt Total	(40)
Parent Company [Member]
Debt Instrument [Line Items]
Recourse Debt Total	$ 4,630
Parent Company [Member] | 8.00% Senior Unsecured Note Due 2017 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		8.00%
Parent Company [Member] | Senior Unsecured Note LIBOR plus 3% due 2019 | Recourse Debt | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%	3.00%
Recourse Debt Total	$ 0	$ 240
Parent Company [Member] | 8.00% Senior Unsecured Note Due 2020 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		8.00%
Parent Company [Member] | 8.00% Senior Unsecured Note Due 2020 | Recourse Debt | LIBOR
Debt Instrument [Line Items]
Recourse Debt Total	228	$ 469
Parent Company [Member] | 7.375% Senior Notes Due 2021 [Member] [Member] | Recourse Debt
Debt Instrument [Line Items]
Recourse Debt Total	690	966
Parent Company [Member] | Revolving Credit Facility [Member] | Recourse Debt
Debt Instrument [Line Items]
Recourse Debt Total	207	0
Parent Company [Member] | Senior Secured Term Loan due 2022 [Member] | Recourse Debt
Debt Instrument [Line Items]
Recourse Debt Total	$ 521	0
Parent Company [Member] | 4.875% Senior Notes Due 2023 [Member] [Member] | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	4.88%
Recourse Debt Total	$ 713	$ 713
Parent Company [Member] | 4.88% Senior Unsecured Note Due 2023 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate		4.88%
Parent Company [Member] | 5.50% Senior Unsecured Note Due 2024 | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	5.50%	5.50%
Recourse Debt Total	$ 738	$ 738
Parent Company [Member] | 5.50% Unsecured senior notes due 2025 [Domain] | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	5.50%	5.50%
Recourse Debt Total	$ 573	$ 573
Parent Company [Member] | 6.00% senior notes due 2026 [Domain] | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	6.00%	6.00%
Recourse Debt Total	$ 500	$ 500
Parent Company [Member] | 5.125% Senior Notes Due 2027 [Member] | Recourse Debt
Debt Instrument [Line Items]
Interest Rate	5.13%
Recourse Debt Total	$ 500	0
Parent Company [Member] | Unamortized (discount) premium & debt issuance (costs), net
Debt Instrument [Line Items]
Recourse Debt Total	$ (40)	$ (45)

Debt (Recourse Debt Net Princip

Debt (Recourse Debt Net Principal Amounts Due Over Five Years) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Details [Line Items]
Recourse Debt Total	$ 4,630	$ 4,671
Unamortized (discounts)/premiums & debt issuance (costs)
Debt Details [Line Items]
Recourse Debt Total	(40)
Parent Company [Member]
Debt Details [Line Items]
Recourse Debt Total	4,630
Parent Company [Member] | 2018
Debt Details [Line Items]
Recourse Debt Total	5
Parent Company [Member] | 2019
Debt Details [Line Items]
Recourse Debt Total	5
Parent Company [Member] | 2020
Debt Details [Line Items]
Recourse Debt Total	234
Parent Company [Member] | 2021
Debt Details [Line Items]
Recourse Debt Total	902
Parent Company [Member] | 2022
Debt Details [Line Items]
Recourse Debt Total	500
Parent Company [Member] | Thereafter
Debt Details [Line Items]
Recourse Debt Total	3,024
Parent Company [Member] | Unamortized (discounts)/premiums & debt issuance (costs)
Debt Details [Line Items]
Recourse Debt Total	$ (40)	$ (45)

Debt (Recourse Debt Narrative)

Debt (Recourse Debt Narrative) (Details) - USD ($) $ in Millions

1 Months Ended

3 Months Ended

9 Months Ended

12 Months Ended

Mar. 31, 2017

May 31, 2016

Jan. 31, 2016

Sep. 30, 2016

Sep. 30, 2017

Sep. 30, 2016

Dec. 31, 2017

Dec. 31, 2016

Dec. 31, 2015

Mar. 01, 2017

May 16, 2016

Jan. 01, 2016

Debt Instrument [Line Items]

Debt terminated amount

$ 125

Loss on extinguishment of debt

$ 68

$ 13

$ 182

8.0% Senior Notes Due 2020 [Domain]

Debt Instrument [Line Items]

Debt terminated amount

$ 24

Senior Unsecured Note LIBOR plus 3% due 2019

Debt Instrument [Line Items]

Loss on extinguishment of debt

$ 4

7.375% Senior Notes Due 2021 [Member] [Member]

Debt Instrument [Line Items]

Debt terminated amount

$ 276

LIBOR 2.00% Senior Notes Due in 2022 [Member]

Debt Instrument [Line Items]

Loss on extinguishment of debt

$ 6

Senior Notes [Member] | 5.125% Senior Notes Due 2017 [Member]

Debt Instrument [Line Items]

Debt face amount

500

Senior Notes [Member] | 8.0% Senior Notes Due 2017

Debt Instrument [Line Items]

Debt terminated amount

$ 181

Senior Notes [Member] | 8.0% Senior Notes Due 2020 [Domain]

Debt Instrument [Line Items]

Debt terminated amount

217

Senior Notes [Member] | 6.00% senior notes due 2026 [Domain]

Debt Instrument [Line Items]

Stated interest rate

6.00%

Debt face amount

$ 500

Senior Notes [Member] | Senior Unsecured Note LIBOR plus 3% due 2019

Debt Instrument [Line Items]

Debt terminated amount

$ 495

240

Senior Notes [Member] | LIBOR 2.00% Senior Notes Due in 2022 [Member]

Debt Instrument [Line Items]

Debt terminated amount

$ 517

Debt face amount

525

Recourse Debt

Recourse Debt Covenants and Guarantees:

Percentage of capital stock of foreign subsidiaries securing obligations

65.00%

Covenants, sale of guarantor or its subsidiaries percentage of proceeds used to repay debt

60.00%

Covenants, sale of guarantor or its subsidiaries percentage of proceeds used to repay debt if debt to cash flow is less than 5

50.00%

Minimum ratio of operating cash flow to interest charges

1.3

Maximum ratio of debt to cash flow

7.5

Unsecured Debt [Member] | 5.125% Senior Notes Due 2027 [Member]

Debt Instrument [Line Items]

Stated interest rate

5.125%

Unsecured Debt [Member] | 8.0% Senior Notes Due 2017

Debt Instrument [Line Items]

Stated interest rate

8.00%

8.00%

Loss on extinguishment of debt

$ 16

Unsecured Debt [Member] | 8.0% Senior Notes Due 2020 [Domain]

Debt Instrument [Line Items]

Stated interest rate

8.00%

8.00%

Loss on extinguishment of debt

$ 47

Unsecured Debt [Member] | Senior Unsecured Note LIBOR plus 3% due 2019

Debt Instrument [Line Items]

Loss on extinguishment of debt

$ 36

Unsecured Debt [Member] | 7.375% Senior Notes Due 2021 [Member] [Member]

Debt Instrument [Line Items]

Stated interest rate

7.375%

7.375%

Unsecured Debt [Member] | 4.875% Senior Notes Due 2023 [Member] [Member]

Debt Instrument [Line Items]

Stated interest rate

4.875%

Loss on extinguishment of debt

$ (7)

Unsecured Debt [Member] | 5.5% Senior Notes Due 2024 [Member] [Member]

Debt Instrument [Line Items]

Stated interest rate

5.50%

Unsecured Debt [Member] | 5.5% Senior Notes Due 2025 [Member] [Member]

Debt Instrument [Line Items]

Stated interest rate

5.50%

Parent Company [Member]

Debt Instrument [Line Items]

Loss on extinguishment of debt

$ 92

$ 14

$ 105

Debt (Term Convertible Trust Se

Debt (Term Convertible Trust Securities) (Details) $ / shares in Units, security in Thousands, $ in Millions	24 Months Ended
	Dec. 31, 2000USD ($)	Dec. 31, 1999USD ($)security$ / shares
Debt Disclosure [Abstract]
Term convertible preferred securities issued by special purpose business trust | security		10,350
Current redemption value of term convertible preferred securities issued by special purpose business trust | $ / shares		$ 50
Term convertible preferred securities issued by special purpose business trust par per share | $ / shares		$ 0.844
Term convertible preferred securities issued by special purpose business trust total proceeds | $	$ 517
Junior subordinated convertible debentures purchased with proceeds from issuance of term convertible preferred securities | $		$ 517
Term convertible preferred securities dividend rate		6.75%

Commitments (Leases, Future Min

Commitments (Leases, Future Minimum Payments Due) (Details) $ in Millions	Dec. 31, 2017USD ($)
Future Commitments for Capital Leases:
2,018	$ 2
2,019	1
2,020	1
2,021	1
2,022	1
Thereafter	12
Total	18
Less: Imputed interest	(10)
Present value of total minimum lease payments	8
Future Commitments for Operating Leases:
2,018	58
2,019	58
2,020	58
2,021	59
2,022	58
Thereafter	644
Total	$ 935

Commitments (Long-Term Purchase

Commitments (Long-Term Purchase Commitments) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Electricity Purchase Contracts
Long-Term Purchase Commitment [Line Items]
Purchases Under Long Term Contracts	$ 747	$ 420	$ 545
Future Commitments 2018	581
Future Commitments 2019	508
Future Commitments 2020	440
Future Commitments 2021	469
Future Commitments 2022	438
Future Commitments Thereafter	2,065
Future Commitments Total	4,501
Fuel Purchase Contracts
Long-Term Purchase Commitment [Line Items]
Purchases Under Long Term Contracts	1,619	1,790	1,262
Future Commitments 2018	1,759
Future Commitments 2019	1,051
Future Commitments 2020	591
Future Commitments 2021	538
Future Commitments 2022	454
Future Commitments Thereafter	1,466
Future Commitments Total	5,859
Other Purchase Contracts
Long-Term Purchase Commitment [Line Items]
Purchases Under Long Term Contracts	1,945	$ 817	$ 1,833
Future Commitments 2018	1,488
Future Commitments 2019	931
Future Commitments 2020	470
Future Commitments 2021	234
Future Commitments 2022	547
Future Commitments Thereafter	1,314
Future Commitments Total	$ 4,984

Commitments (Narrative) (Detail

Commitments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Leases, Operating [Abstract]
Operating lease and rental expense	$ 61	$ 61	$ 45
Leases Capital [Abstract]
Capital leased assets, gross	$ 27	$ 22

Contingencies (Loss Contingenci

Contingencies (Loss Contingencies) (Details) $ in Millions		12 Months Ended
		Dec. 31, 2017USD ($)agreement	Dec. 31, 2016USD ($)
Loss Contingencies [Line Items]
Amount (in millions)		$ 930
Obligations made by the Parent Company associated with non-recourse debt		$ 0
Number of Agreements | agreement		47
Guarantees [Member]
Loss Contingencies [Line Items]
Amount (in millions)		$ 815
Number of Agreements | agreement		21
Indemnification Agreement [Member]
Loss Contingencies [Line Items]
Amount (in millions)	[1]	$ 27
Number of Agreements | agreement	[1]	1
Environmental
Environmental Contingencies
Liability recorded for projected environmental remediation costs		$ 5	$ 9
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		18
Litigation
Litigation Contingencies
Aggregate reserves for claims deemed both probable and reasonably estimable		$ 50	$ 59
Parent Company
Loss Contingencies [Line Items]
Letter Of Credit Fee Range Maximum		2.25%
Letter Of Credit Fee Range Minimum		0.25%
Unsecured Debt [Member] | Financial Standby Letter of Credit [Member]
Loss Contingencies [Line Items]
Amount (in millions)		$ 52
Number of Agreements | agreement		4
Secured Debt [Member] | Standby Letters of Credit [Member]
Loss Contingencies [Line Items]
Amount (in millions)		$ 36
Number of Agreements | agreement		21
Minimum [Member] | Indemnification Agreement [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss
Minimum [Member] | Guarantee Obligations [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		1
Minimum [Member] | Litigation
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		140
Minimum [Member] | Unsecured Debt [Member] | Financial Standby Letter of Credit [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		2
Minimum [Member] | Secured Debt [Member] | Financial Standby Letter of Credit [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		1
Maximum [Member] | Indemnification Agreement [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		27
Maximum [Member] | Guarantee Obligations [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		272
Maximum [Member] | Litigation
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		173
Maximum [Member] | Unsecured Debt [Member] | Financial Standby Letter of Credit [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		26
Maximum [Member] | Secured Debt [Member] | Financial Standby Letter of Credit [Member]
Litigation Contingencies
Loss Contingency, Estimate of Possible Loss		$ 13
[1]	Excludes normal and customary representations and warranties in agreements for the sale of assets (including ownership in associated legal entities) where the associated risk is considered to be nominal.

Benefit Plans (Narrative) (Deta

Benefit Plans (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)plan	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, number of plans	4
Defined contribution plan, award vesting period	5 years
Defined contribution plan contributions | $	$ 23	$ 15	$ 18
Defined benefit plan, number of plans disclosure	31
U.S. Non-Union Number of Defined Contribution Plans	2
Parent Company Number of Defined Contribution Plans	1
IPL Number of Non-Union and Union Defined Contribution Plans	1
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, number of plans disclosure	5

Benefit Plans (Net Funded Statu

Benefit Plans (Net Funded Status) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	$ (22)	$ (19)
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant	1	1
CHANGE IN PROJECTED BENEFIT OBLIGATION:
Benefit obligation, beginning period	411	374
Service cost	10	9	$ 10
Interest cost	23	21	23
Defined Benefit Plan, Benefit Obligation, Interest cost	22
Plan amendments	(1)	(4)
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment	0	0
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	2	0
Actuarial loss	(29)	(58)
Effect of foreign currency exchange rate changes	22	(29)
Benefit obligation, ending period	470	411	374
CHANGE IN PLAN ASSETS:
Fair value of plan assets, beginning period	402	379
Actual return on plan assets	31	59
Employer contributions	18	18
Defined Benefit Plan, Plan Assets, Payment for Settlement	(2)	0
Effect of foreign currency exchange rate changes	27	(36)
Fair value of plan assets, ending period	455	402	379
Funded status as of December 31	(15)	(9)
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	1	1
Defined Benefit Plan, Plan Assets, Benefits Paid	(22)	(19)
UNITED STATES
CHANGE IN PROJECTED BENEFIT OBLIGATION:
Benefit obligation, beginning period	1,188	1,172
Service cost	13	13	16
Interest cost	41	42	48
Plan amendments	1	0
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment	3	2
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	0	0
Actuarial loss	(82)	(19)
Effect of foreign currency exchange rate changes	0	0
Benefit obligation, ending period	1,257	1,188	1,172
CHANGE IN PLAN ASSETS:
Fair value of plan assets, beginning period	1,044	1,021
Actual return on plan assets	141	61
Employer contributions	13	22
Defined Benefit Plan, Plan Assets, Payment for Settlement	0	0
Effect of foreign currency exchange rate changes	0	0
Fair value of plan assets, ending period	1,127	1,044	$ 1,021
Funded status as of December 31	(130)	(144)
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	0	0
Defined Benefit Plan, Plan Assets, Benefits Paid	$ (71)	$ (60)

Benefit Plans (Amounts Recogniz

Benefit Plans (Amounts Recognized in the Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
AMOUNTS RECOGNIZED ON THE CONSOLIDATED BALANCE SHEETS
Accrued benefit liability—noncurrent	$ (230)	$ (237)
Foreign Plan [Member]
AMOUNTS RECOGNIZED ON THE CONSOLIDATED BALANCE SHEETS
Noncurrent assets	69	60
Accrued benefit liability—current	(6)	(5)
Accrued benefit liability—noncurrent	(78)	(64)
Net amount recognized at end of year	(15)	(9)
UNITED STATES
AMOUNTS RECOGNIZED ON THE CONSOLIDATED BALANCE SHEETS
Noncurrent assets	0	0
Accrued benefit liability—current	0	0
Accrued benefit liability—noncurrent	(130)	(144)
Net amount recognized at end of year	$ (130)	$ (144)

Benefit Plans (Accumulated Bene

Benefit Plans (Accumulated Benefit Obligation) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated Benefit Obligation	$ 433	$ 384
Information for pension plans with an accumulated benefit obligation in excess of plan assets:
Projected benefit obligation	109	90
Accumulated benefit obligation	97	80
Fair value of plan assets	33	25
Information for pension plans with a projected benefit obligation in excess of plan assets:
Projected benefit obligation	238	212
Fair value of plan assets	154	142
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Accumulated Benefit Obligation	1,236	1,167
Information for pension plans with an accumulated benefit obligation in excess of plan assets:
Projected benefit obligation	1,257	1,188
Accumulated benefit obligation	1,236	1,167
Fair value of plan assets	1,127	1,044
Information for pension plans with a projected benefit obligation in excess of plan assets:
Projected benefit obligation	1,257	1,188
Fair value of plan assets	$ 1,127	$ 1,044

Benefit Plans Benefit Plans (We

Benefit Plans Benefit Plans (Weighted Average Assumptions) (Details)		12 Months Ended
		Dec. 31, 2017Rate	Dec. 31, 2016Rate
Foreign Plan [Member]
Benefit Obligation:
Discount rate		5.23%	5.83%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	[1]	5.83%	6.10%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets		5.30%	5.09%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase		4.86%	4.45%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase		4.65%	4.86%
UNITED STATES
Benefit Obligation:
Discount rate		3.67%	4.28%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate		4.28%	4.44%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets		6.67%	6.67%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase		3.34%	3.34%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase		3.34%	3.34%
[1]	Includes an inflation factor that is used to calculate future periodic benefit cost, but is not used to calculate the benefit obligation.

Benefit Plans (Impact of One Po

Benefit Plans (Impact of One Point Change in Assumptions) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Defined Benefit Plan Assumptions Sensitivity To Changes [Abstract]
Increase of 1% in the discount rate	$ (13)
Decrease of 1% in the discount rate	12
Increase of 1% in the long-term rate of return on plan assets	(15)
Decrease of 1% in the long-term rate of return on plan assets	$ 15

Benefit Plans (Net Periodic Ben

Benefit Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Foreign Plan [Member]
Components of Net Periodic Benefit Cost:
Service cost	$ 10	$ 9	$ 10
Interest cost	23	21	23
Expected return on plan assets	(21)	(19)	(20)
Amortization of prior service cost	0	(1)	0
Amortization of net loss	2	2	2
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment	0	0	0
Total pension cost	14	12	15
UNITED STATES
Components of Net Periodic Benefit Cost:
Service cost	13	13	16
Interest cost	41	42	48
Expected return on plan assets	(69)	(68)	(70)
Amortization of prior service cost	6	7	7
Amortization of net loss	18	18	20
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment	4	4	0
Total pension cost	$ 13	$ 16	$ 21

Benefit Plans (Accumulated Othe

Benefit Plans (Accumulated Other Comprehensive Income (Loss)) (Details) $ in Millions	Dec. 31, 2017USD ($)
UNITED STATES
Accumulated Other Comprehensive Income (Loss)
Prior service cost	$ (1)
Unrecognized net actuarial loss	(22)
Total	(23)
Amounts expected to be reclassified to earnings in next fiscal year
Prior service cost	0
Unrecognized net actuarial loss	(2)
Total	(2)
Foreign Plan [Member]
Accumulated Other Comprehensive Income (Loss)
Prior service cost	1
Unrecognized net actuarial loss	(81)
Total	(80)
Amounts expected to be reclassified to earnings in next fiscal year
Prior service cost	0
Unrecognized net actuarial loss	(3)
Total	$ (3)

Benefit Plans (Plan Asset Alloc

Benefit Plans (Plan Asset Allocations) (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 455,000,000	$ 402,000,000	$ 379,000,000
Percentage of Plan Assets	100.00%	100.00%
Foreign Plan [Member] | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	4.00%
Percentage of Plan Assets	4.61%	18.66%
Foreign Plan [Member] | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	93.00%
Percentage of Plan Assets	93.10%	78.35%
Foreign Plan [Member] | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 2,000,000	$ 3,000,000
Target Allocations	0.00%
Percentage of Plan Assets	0.44%	0.75%
Foreign Plan [Member] | Other
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	3.00%
Percentage of Plan Assets	1.85%	2.24%
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 1,127,000,000	$ 1,044,000,000	$ 1,021,000,000
Percentage of Plan Assets	100.00%	100.00%
UNITED STATES | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	33.00%
Percentage of Plan Assets	31.90%	50.96%
UNITED STATES | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	65.00%
Percentage of Plan Assets	64.53%	45.88%
UNITED STATES | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 36,000,000	$ 33,000,000
Target Allocations	2.00%
Percentage of Plan Assets	3.20%	3.16%
UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 4,000,000	$ 0
UNITED STATES | Other
Defined Benefit Plan Disclosure [Line Items]
Target Allocations	0.00%
Percentage of Plan Assets	0.37%	0.00%
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 355,000,000	$ 300,000,000
Fair Value, Inputs, Level 1 [Member] | Foreign Plan [Member] | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	1,091,000,000	1,011,000,000
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 1 [Member] | UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	4,000,000	0
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	90,000,000	90,000,000
Fair Value, Inputs, Level 2 [Member] | Foreign Plan [Member] | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 2 [Member] | UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	36,000,000	33,000,000
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	36,000,000	33,000,000
Fair Value, Inputs, Level 2 [Member] | UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	10,000,000	12,000,000
Fair Value, Inputs, Level 3 [Member] | Foreign Plan [Member] | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	2,000,000	3,000,000
Fair Value, Inputs, Level 3 [Member] | UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Real estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	0
Fair Value, Inputs, Level 3 [Member] | UNITED STATES | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	$ 0	$ 0

Benefit Plans (Fair Value of Pl

Benefit Plans (Fair Value of Plan Assets) (Details) - USD ($)		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		$ 455,000,000	$ 402,000,000	$ 379,000,000
Foreign Plan [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		355,000,000	300,000,000
Foreign Plan [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		90,000,000	90,000,000
Foreign Plan [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		10,000,000	12,000,000
Foreign Plan [Member] | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		20,000,000	71,000,000
Foreign Plan [Member] | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		20,000,000	71,000,000
Foreign Plan [Member] | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Private equity
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,000,000	4,000,000
Foreign Plan [Member] | Private equity | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Private equity | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Private equity | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,000,000	4,000,000
Foreign Plan [Member] | Government debt securities
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		11,000,000	10,000,000
Foreign Plan [Member] | Government debt securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		11,000,000	10,000,000
Foreign Plan [Member] | Government debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Government debt securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets	[1]	413,000,000	305,000,000
Foreign Plan [Member] | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		323,000,000	215,000,000
Foreign Plan [Member] | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		90,000,000	90,000,000
Foreign Plan [Member] | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Real estate
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		2,000,000	3,000,000
Foreign Plan [Member] | Real estate | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Real estate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Real estate | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		2,000,000	3,000,000
Foreign Plan [Member] | Participant loans
Defined Benefit Plan Disclosure [Line Items]
Total plan assets	[2]	0	2,000,000
Foreign Plan [Member] | Participant loans | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Participant loans | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Participant loans | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	2,000,000
Foreign Plan [Member] | Other assets
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		8,000,000	7,000,000
Foreign Plan [Member] | Other assets | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,000,000	4,000,000
Foreign Plan [Member] | Other assets | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
Foreign Plan [Member] | Other assets | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		7,000,000	3,000,000
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,127,000,000	1,044,000,000	$ 1,021,000,000
UNITED STATES | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		1,091,000,000	1,011,000,000
UNITED STATES | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		36,000,000	33,000,000
UNITED STATES | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		359,000,000	532,000,000
UNITED STATES | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		359,000,000	532,000,000
UNITED STATES | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Government debt securities
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		135,000,000	86,000,000
UNITED STATES | Government debt securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		135,000,000	86,000,000
UNITED STATES | Government debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Government debt securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Total plan assets	[3]	593,000,000	393,000,000
UNITED STATES | Mutual funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		593,000,000	393,000,000
UNITED STATES | Mutual funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Mutual funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Real estate
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		36,000,000	33,000,000
UNITED STATES | Real estate | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		0	0
UNITED STATES | Real estate | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		36,000,000	33,000,000
UNITED STATES | Real estate | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total plan assets		$ 0	$ 0
[1]	Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment
[2]	Loans to participants are stated at cost, which approximates fair value
[3]	Mutual funds categorized as debt securities consist of mutual funds for which debt securities are the primary underlying investment

Benefit Plans (Expected Future

Benefit Plans (Expected Future Benefit Payments) (Details) $ in Millions	Dec. 31, 2017USD ($)
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected employer contribution in 2018	$ 15
Expected benefit payments for fiscal year ending:
2,017	23
2,018	23
2,019	25
2,020	26
2,021	27
2023 - 2027	170
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Expected employer contribution in 2018	39
Expected benefit payments for fiscal year ending:
2,017	71
2,018	73
2,019	74
2,020	75
2,021	76
2023 - 2027	$ 380

Equity (Transactions with Nonco

Equity (Transactions with Noncontrolling Interests) (Details) - USD ($)

Sep. 28, 2017

Feb. 18, 2016

Nov. 18, 2015

Feb. 11, 2015

Dec. 31, 2015

Nov. 30, 2015

Feb. 28, 2015

Dec. 31, 2014

Mar. 31, 2016

Dec. 31, 2015

Jun. 30, 2015

Dec. 31, 2017

Dec. 31, 2016

Dec. 31, 2015

Dec. 17, 2017

Apr. 01, 2015

Jun. 25, 2014

Noncontrolling Interest [Line Items]

Gain (Loss) on Disposition of Business

$ (52,000,000)

$ 29,000,000

$ 29,000,000

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

6.70%

Stockholders' Equity Attributable to Parent

$ 2,465,000,000

2,794,000,000

Additional Paid in Capital

8,501,000,000

8,592,000,000

Accumulated Other Comprehensive Income (Loss), Net of Tax

$ (3,883,000,000)

$ (3,883,000,000)

(1,876,000,000)

$ (2,756,000,000)

(3,883,000,000)

Alto Maipo [Member]

Noncontrolling Interest [Line Items]

Gain (Loss) on Disposition of Business

$ 0

Business Acquisition, Percentage of Voting Interests Acquired

40.00%

Noncontrolling Interest, Ownership Percentage by Parent

62.00%

Stockholders' Equity Attributable to Parent

$ 196,000,000

Additional Paid in Capital

229,000,000

Accumulated Other Comprehensive Income (Loss), Net of Tax

$ (33,000,000)

Masinloc Subsidiary [Member]

Noncontrolling Interest [Line Items]

Divestiture of Businesses, Portion Contingent Upon Achievement of Certain Restructuring Efficiencies

$ 23,000,000

Disposal Group Not Discontinued Operation Ownership Interest Sold

100.00%

51.00%

45.00%

Dominican Republic

Noncontrolling Interest [Line Items]

Gain (Loss) on Disposition of Business

$ 0

0

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

5.00%

10.00%

Proceeds from divestiture of business

$ 60,000,000

Sale Agreement, Buyer Option To Purchase Ownership Interest, Sales Price

$ 18,000,000

Gain on Disposition of Stock in Subsidiary, Recorded to APIC

$ 7,000,000

$ 25,000,000

Cachagua [Member]

Noncontrolling Interest [Line Items]

Noncontrolling Interest, Ownership Percentage by Parent

99.90%

Gener Subsidiary [Member]

Noncontrolling Interest [Line Items]

Gain on Disposition of Stock in Subsidiary, Recorded to APIC

$ 24,000,000

Sale of Stock, Consideration Received Per Transaction

$ 145,000,000

Sale of Stock, Percentage of Ownership before Transaction

70.70%

Sale of Stock, Percentage of Ownership after Transaction

66.70%

IPP4 [Member]

Noncontrolling Interest [Line Items]

Noncontrolling Interest, Ownership Percentage by Parent

36.00%

AES US Investment, Inc.

Noncontrolling Interest [Line Items]

Investment In Affiliate Ownership Percentage Sold

15.00%

Sale of Stock, Consideration Received Per Transaction

$ 247,000,000

IPALCO Enterprises, Inc. [Member]

Noncontrolling Interest [Line Items]

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

24.90%

sales agreement, Buyer option to purchase ownership interest, exercised

$ 214,000,000

Gener Subsidiary [Member]

Noncontrolling Interest [Line Items]

Gain (Loss) on Disposition of Business

$ 0

Disposal Group Not Discontinued Operation Ownership Interest Sold

4.00%

Jordan [Member]

Noncontrolling Interest [Line Items]

Disposal Group, Including Discontinued Operation, Consideration

$ 21,000,000

Gain (Loss) on Disposition of Business

$ 4,000,000

Disposal Group Not Discontinued Operation Ownership Interest Sold

40.00%

Acquire additional shares through 2016

Noncontrolling Interest [Line Items]

Investment Options, acquisition percentage

17.65%

Acquire additional shares through December 31, 2017 [Member] | Dominican Republic

Noncontrolling Interest [Line Items]

Sale Agreement, Buyer Option To Purchase Ownership Interest, Sales Price

$ 125,000,000

Additional Paid-in Capital [Member]

Noncontrolling Interest [Line Items]

Sale of subsidiary shares to noncontrolling interests

13,000,000

$ 84,000,000

323,000,000

Additional Paid-in Capital [Member] | AES Brasiliana [Domain]

Noncontrolling Interest [Line Items]

Other Restructuring Costs

27,000,000

Additional Paid-in Capital [Member] | IPALCO Enterprises, Inc. [Member]

Noncontrolling Interest [Line Items]

Business Combination, Separately Recognized Transactions, Additional Disclosures, Issuance Costs Not Expensed

$ 84,000,000

Retained Earnings (Accumulated Deficit)

Noncontrolling Interest [Line Items]

Sale of subsidiary shares to noncontrolling interests

0

(84,000,000)

(377,000,000)

Retained Earnings (Accumulated Deficit) | IPALCO Enterprises, Inc. [Member]

Noncontrolling Interest [Line Items]

Sale of subsidiary shares to noncontrolling interests

$ (84,000,000)

$ (377,000,000)

(84,000,000)

[1]

(377,000,000)

[1]

Noncontrolling Interest [Member]

Noncontrolling Interest [Line Items]

Sale of subsidiary shares to noncontrolling interests

$ 83,000,000

$ 17,000,000

$ 119,000,000

Mitsui Ltd [Member] | IPP4 [Member]

Noncontrolling Interest [Line Items]

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

40.00%

Nebras Power Q.S.C [Member] | IPP4 [Member]

Noncontrolling Interest [Line Items]

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

24.00%

[1]

See Note 17—Redeemable stock of subsidiaries for further information on increase in paid-in-capital transferred to redeemable stock of subsidiaries.

Equity Equity - Net Income (Los

Equity Equity - Net Income (Loss) Attributable to The AES Corporation (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Dec. 31, 2017	Dec. 31, 2016		Dec. 31, 2015
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Net income (loss) attributable to The AES Corporation	$ (1,342)	$ 152	$ 53	$ (24)	$ (949)	$ 175	$ (482)	$ 126		$ (1,161)	$ (1,130)		$ 306
Transfers from the noncontrolling interest:
Increase (decrease) in The AES Corporation's paid-in-capital for purchase of subsidiary shares										240	(2)
Net transfers (to) from noncontrolling interest										253	(2)		(54)
Change from net income (loss) attributable to The AES Corporation and transfers (to) from noncontrolling interests										(908)	(1,132)		252
Additional Paid-in Capital [Member]
Transfers from the noncontrolling interest:
Net increase in The AES Corporation's paid-in capital for sale of subsidiary shares										13	84		323
Increase (decrease) in The AES Corporation's paid-in-capital for purchase of subsidiary shares										240	(2)		0
Retained Earnings [Member]
Transfers from the noncontrolling interest:
Net increase in The AES Corporation's paid-in capital for sale of subsidiary shares										0	(84)		(377)
Increase (decrease) in The AES Corporation's paid-in-capital for purchase of subsidiary shares										$ 0	0
IPALCO Enterprises, Inc. [Member] | Retained Earnings [Member]
Transfers from the noncontrolling interest:
Net increase in The AES Corporation's paid-in capital for sale of subsidiary shares								$ (84)	$ (377)		$ (84)	[1]	$ (377)	[1]
[1]	See Note 17—Redeemable stock of subsidiaries for further information on increase in paid-in-capital transferred to redeemable stock of subsidiaries.

Equity (Accumulated Other Compr

Equity (Accumulated Other Comprehensive Loss) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Beginning Balance	$ (2,147,000,000)	$ (3,256,000,000)
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax, Beginning Balance	(323,000,000)	(353,000,000)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax, Beginning Balance	(286,000,000)	(274,000,000)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance	(2,756,000,000)	(3,883,000,000)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(15,000,000)	106,000,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	928,000,000	1,021,000,000
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	634,000,000	1,181,000,000	$ (1,019,000,000)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	38,000,000	42,000,000	9,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	247,000,000	(187,000,000)	77,000,000
Other Comprehensive Income (Loss), Net of Tax	919,000,000	1,036,000,000	(933,000,000)
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Ending Balance	(1,486,000,000)	(2,147,000,000)	(3,256,000,000)
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax, Ending Balance	(333,000,000)	(323,000,000)	(353,000,000)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax, Ending Balance	(57,000,000)	(286,000,000)	(274,000,000)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	(1,876,000,000)	(2,756,000,000)	(3,883,000,000)
Available-for-Sale securities, net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	18,000,000	117,000,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	643,000,000	992,000,000
Unrealized derivative gains (losses), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(14,000,000)	2,000,000
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	37,000,000	28,000,000
Unfunded pension obligations, net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(19,000,000)	(13,000,000)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	248,000,000	1,000,000
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	661,000,000	1,109,000,000	(674,000,000)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	23,000,000	30,000,000	43,000,000
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	229,000,000	(12,000,000)	21,000,000
Other Comprehensive Income (Loss), Net of Tax	913,000,000	$ 1,127,000,000	(610,000,000)
Cumulative Effect of New Accounting Principle in Period of Adoption	0		$ 13,000,000
Alto Maipo [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Ending Balance	0
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax, Ending Balance	(33,000,000)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax, Ending Balance	0
Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance	$ (33,000,000)

Equity (Reclassifications Out o

Equity (Reclassifications Out of AOCL) (Details) - USD ($) $ in Millions	3 Months Ended																12 Months Ended
	Dec. 31, 2017		Sep. 30, 2017		Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2016		Sep. 30, 2016		Jun. 30, 2016		Mar. 31, 2016		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-regulated revenue																	$ 7,421	$ 6,971	$ 8,020
Regulated cost of sales																	(2,656)	(2,844)	(3,074)
Non-regulated cost of sales																	(5,410)	(5,057)	(5,523)
General and administrative expenses																	215	194	196
Other Expenses																	57	79	24
Interest expense																	(1,170)	(1,134)	(1,145)
Gain (loss) on disposal and sale of businesses																	(52)	29	29
Foreign currency transaction gains																	42	(15)	106
Income from continuing operations before taxes and equity in earnings of affiliates																	771	187	989
Income tax expense																	(990)	(32)	(412)
Net equity in earnings of affiliates																	71	36	105
Income (loss) from continuing operations	$ (622)	[1]	$ 236	[1]	$ 141	[1]	$ 97	[1]	$ (136)	[2]	$ 238	[2]	$ 2	[2]	$ 87	[2]	(148)	191	682
Net loss from disposal and impairments of discontinued operations																	(611)	(1,119)	0
Net income (loss)	(1,286)		261		150		98		(693)		229		(387)		74		(777)	(777)	762
Less: (Income) from continuing operations attributable to noncontrolling interests																	(359)	(211)	(364)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest																	(25)	(142)	(92)
Net income attributable to The AES Corporation	$ (1,342)		$ 152		$ 53		$ (24)		$ (949)		$ 175		$ (482)		$ 126		(1,161)	(1,130)	306
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income attributable to The AES Corporation																	(928)	(1,021)	(50)
Available-for-Sale securities, net | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gain (loss) on disposal and sale of businesses																	(188)	0	0
Net loss from disposal and impairments of discontinued operations																	(455)	(992)	0
Net income attributable to The AES Corporation																	(643)	(992)	0
Unrealized derivative gains (losses), net | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-regulated revenue																	25	111	43
Non-regulated cost of sales																	(12)	(57)	(14)
Interest expense																	(79)	(107)	(112)
Gain (loss) on disposal and sale of businesses																	0	0	(4)
Foreign currency transaction gains																	15	8	12
Income from continuing operations before taxes and equity in earnings of affiliates																	(51)	(45)	(75)
Income tax expense																	1	8	11
Net equity in earnings of affiliates																	0	0	(2)
Income (loss) from continuing operations																	(50)	(37)	(66)
Less: (Income) from continuing operations attributable to noncontrolling interests																	13	9	18
Net income attributable to The AES Corporation																	(37)	(28)	(48)
Amortization of defined benefit pension actuarial losses, net | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Non-regulated cost of sales																	1	0	2
General and administrative expenses																	(1)	(1)	(2)
Other Expenses																	0	(1)	0
Income from continuing operations before taxes and equity in earnings of affiliates																	0	(2)	0
Income tax expense																	0	3	9
Income (loss) from continuing operations																	0	1	9
Net loss from disposal and impairments of discontinued operations																	(266)	(11)	(25)
Net income (loss)																	(266)	(10)	(16)
Less: (Income) from continuing operations attributable to noncontrolling interests																	0	9	14
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest																	18	0	0
Net income attributable to The AES Corporation																	$ (248)	$ (1)	$ (2)
[1]	Includes pre-tax impairment expense of $168 million, $90 million, $2 million and $277 million, for the first, second, third and fourth quarters of 2017, respectively. See Note 19—Asset Impairment Expense for further discussion.
[2]	Includes pre-tax impairment expense of $159 million, $235 million, $79 million and $623 million, for the first, second, third and fourth quarters of 2016, respectively. See Note 19—Asset Impairment Expense for further discussion.

Equity Equity (Dividends) (Deta

Equity Equity (Dividends) (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 08, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Cash Paid		$ 0.12	$ 0.12	$ 0.12	$ 0.12
Dividends declared on common stock (per share amount)	$ 0.13	$ 0.25	$ 0.12	$ 0	$ 0.12	$ 0.23	$ 0.11	$ 0	$ 0.11	$ 0.49	$ 0.45	$ 0.41
Treasury Stock, Value, Acquired, Cost Method													$ 1,900
Payments for Repurchase of Common Stock										$ 0	$ 79	$ 482
Acquisition of treasury stock (shares)										0			154,300,000
Treasury Stock Acquired, Average Cost Per Share													$ 12.12
Stock Repurchase Program, Remaining Authorized Repurchase Amount		$ 246								$ 246			$ 246
Treasury stock, shares (in shares)		155,924,785				156,878,891				155,924,785	156,878,891		155,924,785

Equity Equity (Stock Repurchase

Equity Equity (Stock Repurchases) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended			90 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 246			$ 246
Treasury Stock, Shares	155,924,785	156,878,891		155,924,785
Acquisition of treasury stock (shares)	0			154,300,000
Payments for Repurchase of Common Stock	$ 0	$ 79	$ 482
Treasury Stock Acquired, Average Cost Per Share				$ 12.12
Treasury Stock, Value, Acquired, Cost Method				$ 1,900

Equity Deconsolidation (Details

Equity Deconsolidation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business	$ (52)	$ 29	$ 29
UK Wind Projects
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business		$ (20)

Segment and Geographic Infor135

Segment and Geographic Information (Details)	12 Months Ended
	Dec. 31, 2017businesssegment
Segment Reporting Information [Line Items]
Number of SBUs | business	5
Number of Operating Segments	5
Number of Reportable Segments	5

Segments and Geographic Info136

Segments and Geographic Information Segment and Geographic Information ( Revenue by Segment) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 2,643	$ 2,693	$ 2,613	$ 2,581	$ 2,660	$ 2,639	$ 2,452	$ 2,530	$ 10,530	$ 10,281	$ 11,260
Corporate, Non-Segment [Member] | Corporate and Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									35	77	31
Intersegment Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									(24)	(23)	(43)
Operating Segments [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									10,530	10,281	11,260
Operating Segments [Member] | UNITED STATES
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									3,229	3,429	3,593
Operating Segments [Member] | ANDES [Domain]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									2,710	2,506	2,489
Operating Segments [Member] | Brazil
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									542	450	962
Operating Segments [Member] | MCAC [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									2,448	2,172	2,353
Operating Segments [Member] | EURASIA [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues									$ 1,590	$ 1,670	$ 1,875

Segments and Geographic Info137

Segments and Geographic Information Segment and Geographic Information (Adjusted Pre-Tax Contributions & Reconcilliation of Income Before Income Taxes) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting Information Adjusted Pretax Contribution		$ 1,017	$ 850	$ 1,151
Reconciliation To Income From Continuing Operations Before Taxes
Unrealized derivative gains		(3)	(9)	(166)
Unrealized foreign currency (gains) losses		(59)	22	95
Disposition/acquisition (gains) losses		123	6	(42)
Impairment losses		542	933	504
Loss on extinguishment of debt		62	29	179
One time restructuring costs	[1]	31	0	0
INCOME FROM CONTINUING OPERATIONS BEFORE TAXES AND EQUITY IN EARNINGS OF AFFILIATES		771	187	989
Net equity in earnings of affiliates		71	36	105
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest		(521)	354	513
Pre-tax contribution		321	(131)	581
Operating Segments | US SBU
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting Information Adjusted Pretax Contribution		361	347	360
Reconciliation To Income From Continuing Operations Before Taxes
Net equity in earnings of affiliates		41	9	0
Operating Segments | Andes SBU
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting Information Adjusted Pretax Contribution		386	390	482
Reconciliation To Income From Continuing Operations Before Taxes
Net equity in earnings of affiliates		28	15	83
Operating Segments | Brazil SBU
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting Information Adjusted Pretax Contribution		60	38	92
Operating Segments | MCAC SBU
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting Information Adjusted Pretax Contribution		340	267	327
Reconciliation To Income From Continuing Operations Before Taxes
Net equity in earnings of affiliates		(4)	(2)	0
Operating Segments | EURASIA [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting Information Adjusted Pretax Contribution		290	283	331
Reconciliation To Income From Continuing Operations Before Taxes
Net equity in earnings of affiliates		9	13	18
Corporate, Non-Segment [Member] | Corporate and Other
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Reporting Information Adjusted Pretax Contribution		(420)	(475)	(441)
Reconciliation To Income From Continuing Operations Before Taxes
Net equity in earnings of affiliates		$ (3)	$ 1	$ 4
[1]	One-time restructuring charges consisting of severance costs related to workforce reductions.

Segments and Geographic Info138

Segments and Geographic Information Segment and Geographic Information (Assets, Depreciation and Amortization and Capital Expenditures ) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total Assets	$ 33,112	$ 36,124	$ 36,545
Depreciation and Amortization	1,169	1,176	1,144
Capital Expenditures	2,356	2,458	2,458
Interest Income	244	245	256
Interest Expense	1,170	1,134	1,145
Investments in and Advances to Affiliates	1,197	621	610
Net Equity in Earnings of Affiliates	71	36	105
Operating Segments [Member] | US SBU
Segment Reporting Information [Line Items]
Total Assets	9,852	9,333	9,800
Depreciation and Amortization	437	471	443
Capital Expenditures	858	809	861
Interest Income	0	0	0
Interest Expense	258	236	262
Investments in and Advances to Affiliates	527	23	1
Net Equity in Earnings of Affiliates	41	9	0
Operating Segments [Member] | Andes SBU
Segment Reporting Information [Line Items]
Total Assets	8,840	8,971	8,594
Depreciation and Amortization	250	218	175
Capital Expenditures	443	538	949
Interest Income	50	57	77
Interest Expense	205	178	154
Investments in and Advances to Affiliates	358	363	345
Net Equity in Earnings of Affiliates	28	15	83
Operating Segments [Member] | Brazil SBU
Segment Reporting Information [Line Items]
Total Assets	2,034	1,516	1,179
Depreciation and Amortization	51	33	39
Capital Expenditures	34	31	47
Interest Income	45	38	31
Interest Expense	92	69	58
Operating Segments [Member] | MCAC SBU
Segment Reporting Information [Line Items]
Total Assets	5,532	5,162	4,820
Depreciation and Amortization	172	165	155
Capital Expenditures	482	480	201
Interest Income	18	11	30
Interest Expense	168	163	179
Investments in and Advances to Affiliates	3	(1)	0
Net Equity in Earnings of Affiliates	(4)	(2)	0
Operating Segments [Member] | EURASIA [Member]
Segment Reporting Information [Line Items]
Total Assets	4,557	5,777	6,200
Depreciation and Amortization	127	149	166
Capital Expenditures	211	279	131
Interest Income	130	139	116
Interest Expense	167	179	158
Investments in and Advances to Affiliates	307	236	248
Net Equity in Earnings of Affiliates	9	13	18
Segment Reconciling Items [Member] | Assets held-for-sale
Segment Reporting Information [Line Items]
Total Assets	2,034	4,936	5,411
Depreciation and Amortization	123	128	146
Capital Expenditures	315	303	252
Corporate, Non-Segment [Member] | Corporate and Other
Segment Reporting Information [Line Items]
Total Assets	263	429	541
Depreciation and Amortization	9	12	20
Capital Expenditures	13	18	17
Interest Income	1	0	2
Interest Expense	280	309	334
Investments in and Advances to Affiliates	2	0	16
Net Equity in Earnings of Affiliates	$ (3)	$ 1	$ 4

Segments and Geographic Info139

Segments and Geographic Information Segment and Geographic Information (Revenue and Assets by Country) (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue		$ 2,643	$ 2,693	$ 2,613	$ 2,581	$ 2,660	$ 2,639	$ 2,452	$ 2,530	$ 10,530	$ 10,281	$ 11,260
Property, plant and equipment, net		20,296				20,415				20,296	20,415
US SBU
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										3,240	3,489	3,597
Property, plant and equipment, net		7,403				7,397				7,403	7,397
Total Non-U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										7,290	6,792	7,663
Property, plant and equipment, net		12,893				13,018				12,893	13,018
Brazil
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										541	450	962
Property, plant and equipment, net		1,286				789				1,286	789
CHILE
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										1,944	1,707	1,523
Property, plant and equipment, net		5,066				4,995				5,066	4,995
Dominican Republic
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										826	614	632
Property, plant and equipment, net		935				914				935	914
El Salvador
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										686	601	736
Property, plant and equipment, net		340				327				340	327
Colombia
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										332	437	557
Property, plant and equipment, net		332				451				332	451
PHILIPPINES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										449	401	406
Property, plant and equipment, net		0				866				0	866
ARGENTINA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										435	359	399
Property, plant and equipment, net		223				195				223	195
Mexico
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										352	342	383
Property, plant and equipment, net		687				699				687	699
Vietnam
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										278	340	233
Property, plant and equipment, net	[1]	2				1				2	1
United Kingdom
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										328	337	396
Property, plant and equipment, net		108				151				108	151
BULGARIA
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										367	334	382
Property, plant and equipment, net		1,290				1,174				1,290	1,174
Panama
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										338	312	297
Property, plant and equipment, net		1,615				1,233				1,615	1,233
Puerto Rico
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										247	301	302
Property, plant and equipment, net		565				583				565	583
JORDAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										95	136	248
Property, plant and equipment, net		431				452				431	452
KAZAKHSTAN
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										67	103	155
Property, plant and equipment, net		0				178				0	178
Other Non-U.S.
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										5	18	$ 52
Property, plant and equipment, net		$ 13				$ 10				$ 13	$ 10
[1]	The Mong Duong II power project is accounted for as a service concession arrangement. Costs of construction of the plant have been deferred in Service concession assets on the Consolidated Balance Sheets.

Share-Based Compensation (Stock

Share-Based Compensation (Stock Option Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax compensation expense	$ 8	$ 10	$ 8

Share-Based Compensation (St141

Share-Based Compensation (Stock Option Activity) (Details) - Stock Options	12 Months Ended
	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Option Grant Price As Percent Of Market Price	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Weighted Average Exercise Price (in dollars per share):
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years

Share-Based Compensation (RSU C

Share-Based Compensation (RSU Compensation Expense) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax compensation expense		$ 8	$ 10	$ 8
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax compensation expense		17	14	13
Tax benefit		(4)	(4)	(3)
compensation expense, net of tax		13	10	10
Total value of RSUs converted	[1]	10	7	16
Total fair value of RSUs vested		$ 15	$ 13	$ 12
[1]	Amount represents fair market value on the date of conversion.

Share-Based Compensation (RSU A

Share-Based Compensation (RSU Activity) (Details) - RSUs - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of straight-line expense, 2015 RSU's	3 years
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 10 months
RSUs (Number of Shares):
Nonvested at beginning of period	3,037
Vested	(1,337)	(1,063)	(954)
Forfeited and expired	(280)
Granted	1,546
Nonvested at end of period	2,966	3,037
Vested and expected to vest at end of period	2,711
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 17
Weighted Average Grant Date Fair Value (in dollars per share):
Nonvested at beginning of period	$ 10.70
Vested	11.37
Forfeited and expired	10.94
Granted	11.93	$ 9.42	$ 12.03
Nonvested at end of period	11.02	$ 10.70
Vested and expected to vest at end of period	$ 11.01
Nonvested at end of period, weighted average remaining vesting term	1 year 5 months

Share-Based Compensation (RSUs

Share-Based Compensation (RSUs Vested and Converted) (Details) - RSUs - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs vested during the year	1,337	1,063	954
RSUs converted during the year, net of shares withheld for taxes	865	705	1,238
Shares withheld for taxes	472	358	549

Share-Based Compensation (PSU C

Share-Based Compensation (PSU Compensation Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSU expense before income tax	$ 8	$ 10	$ 8

Share-Based Compensation (PSU A

Share-Based Compensation (PSU Activity) (Details)	12 Months Ended
	Dec. 31, 2017
Performance Cash Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vesting Rule, Measurement Period	3 years
Maximum [Member] | PSUs
Weighted Average Grant Date Fair Value (in dollars per share):
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Award Payout Range	200.00%

Share-Based Compensation (Narra

Share-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax compensation expense	$ 8	$ 10	$ 8
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option grant price as percent of market price			100.00%
Award vesting period			3 years
Award vesting rights percentage			33.00%
Stock option contractual term			10 years
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax compensation expense	$ 17	$ 14	$ 13
Award vesting period	3 years
Award vesting rights percentage	33.00%
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 17
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 10 months
Estimated forfeiture rate	10.35%
Compensation cost not yet recognized related to current year grants per year	$ 17
Weighted Average Grant Date Fair Value	$ 11.93	$ 9.42	$ 12.03
Performance Cash Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance stock units vesting rule measurement period	3 years
PSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award payout range	0.00%
PSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award payout range	200.00%

Redeemable Stock of Subsidia148

Redeemable Stock of Subsidiaries (Narrative) (Details)

Feb. 11, 2015USD ($)

Jun. 30, 2016USD ($)

Mar. 31, 2016USD ($)

Feb. 28, 2015USD ($)

Mar. 31, 2016USD ($)

Jun. 30, 2015USD ($)

Dec. 31, 2017USD ($)quarterseries$ / shares

Dec. 31, 2016USD ($)quarter$ / shares

Dec. 31, 2015USD ($)

Sep. 30, 2016USD ($)

Apr. 01, 2015USD ($)

Temporary Equity [Line Items]

Temporary Equity, Accretion to Redemption Value

$ 25,000,000

$ 4,000,000

Gain (Loss) on Disposition of Stock in Subsidiary

$ 0

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

6.70%

Temporary equity carrying amount

$ 837,000,000

782,000,000

$ 538,000,000

Temporary Equity, Stock Issued During Period, Value, New Issues

0

134,000,000

Temporary Equity, Other Changes

50,000,000

130,000,000

Temporary Equity, Net Income

(14,000,000)

11,000,000

Colon [Domain]

Temporary Equity [Line Items]

Temporary Equity, Accretion to Redemption Value

1,000,000

Temporary equity carrying amount

159,000,000

100,000,000

Temporary Equity, Other Changes

50,000,000

106,000,000

IPALCO Enterprises, Inc. [Member]

Temporary Equity [Line Items]

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

30.00%

30.00%

Temporary equity carrying amount

618,000,000

618,000,000

Temporary Equity, Stock Issued During Period, Value, New Issues

$ 134,000,000

Temporary Equity, Other Changes

$ 24,000,000

IPL Subsidiary

Temporary Equity [Line Items]

Temporary equity carrying amount

$ 60,000,000

60,000,000

Number of preferred stock series | series

5

Temporary equity annual dividend requirement

$ 3,000,000

$ 3,000,000

Number of consecutive quarters without paid dividends to invoke board of directors election rule | quarter

4

4

IPL Subsidiary | Minimum

Temporary Equity [Line Items]

Temporary equity, redemption price per share | $ / shares

$ 100

$ 100

IPL Subsidiary | Maximum

Temporary Equity [Line Items]

Temporary equity, redemption price per share | $ / shares

118

$ 118

DPL Subsidiary

Temporary Equity [Line Items]

Temporary Equity, Accretion to Redemption Value

$ 5,000,000

Temporary equity carrying amount

18,000,000

Temporary equity annual dividend requirement

Number of quarters cumulative dividends in arrears to invoke board of directors election rule | quarter

DPL Subsidiary | Minimum

Temporary Equity [Line Items]

Temporary equity, redemption price per share | $ / shares

DPL Subsidiary | Maximum

Temporary Equity [Line Items]

Temporary equity, redemption price per share | $ / shares

Other Entity [Member]

Temporary Equity [Line Items]

Temporary equity carrying amount

$ 0

$ 4,000,000

AES US Investment, Inc. [Member]

Temporary Equity [Line Items]

Sale of Stock, Consideration Received Per Transaction

$ 247,000,000

Investment In Affiliate Ownership Percentage Sold

15.00%

IPALCO Enterprises, Inc. [Member]

Temporary Equity [Line Items]

Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners

24.90%

sales agreement, Buyer option to purchase ownership interest, exercised

$ 214,000,000

Additional Paid-in Capital [Member]

Temporary Equity [Line Items]

Temporary Equity, Net Income

[1]

0

0

Sale of subsidiary shares to noncontrolling interests

13,000,000

84,000,000

323,000,000

Additional Paid-in Capital [Member] | IPALCO Enterprises, Inc. [Member]

Temporary Equity [Line Items]

Business Combination, Separately Recognized Transactions, Additional Disclosures, Issuance Costs Not Expensed

84,000,000

Retained Earnings [Member]

Temporary Equity [Line Items]

Temporary Equity, Net Income

[1]

0

0

Sale of subsidiary shares to noncontrolling interests

0

(84,000,000)

(377,000,000)

Retained Earnings [Member] | IPALCO Enterprises, Inc. [Member]

Temporary Equity [Line Items]

Sale of subsidiary shares to noncontrolling interests

$ (84,000,000)

$ (377,000,000)

(84,000,000)

[2]

$ (377,000,000)

[2]

Redeemable Preferred Stock [Member]

Temporary Equity [Line Items]

Temporary Equity Reclassification

(4,000,000)

$ (19,000,000)

Redeemable Preferred Stock [Member] | DPL Subsidiary

Temporary Equity [Line Items]

Redeemable Noncontrolling Interest, Equity, Preferred, Redemption Value

$ 23,000,000

Acquire additional shares through 2016 [Member]

Temporary Equity [Line Items]

Investment Options, acquisition percentage

17.65%

Acquire additional shares through 2016 [Member] | IPALCO Enterprises, Inc. [Member]

Temporary Equity [Line Items]

Sale Agreement, Buyer Option To Purchase Ownership Interest, Sales Price

$ 349,000,000

Other Comprehensive Income (Loss) [Member]

Temporary Equity [Line Items]

Temporary Equity, Other Changes

$ (2,000,000)

$ 6,000,000

[1]

Net income attributable to noncontrolling interest of $398 million and net loss attributable to redeemable stock of subsidiaries of $14 million for the year ended December 31, 2017. Net income attributable to noncontrolling interest of $364 million and net loss attributable to redeemable stock of subsidiaries of $11 million for the year ended December 31, 2016.

[2]

See Note 17—Redeemable stock of subsidiaries for further information on increase in paid-in-capital transferred to redeemable stock of subsidiaries.

Other Income and Expense (Nonop

Other Income and Expense (Nonoperating Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017		Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total other income	$ 120		$ 64	$ 84
Other Income [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Litigation Settlement, Amount Awarded from Other Party	60	[1]	0	0
Public Utilities, Allowance for Funds Used During Construction, Additions	26		29	17
Gain (Loss) on Disposition of Other Assets	1		4	17
Gain (Loss) on Contract Termination	0		0	20
Other	33		31	30
Total other income	$ 120		$ 64	$ 84
[1]	In December 2016, the Company and YPF entered into a settlement in which all parties agreed to give up any and all legal action related to gas supply contracts that were terminated in 2008 and have been in dispute since 2009. In January 2017, the YPF board approved the agreement and paid the Company $60 million, thereby resolving all uncertainties around the dispute.

Other Income and Expense (Other

Other Income and Expense (Other Expense) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of other operating expense [Line Items]
Allowance for other receivables	[1]	$ 0	$ 52	$ 0
Loss On Sale And Disposal Of Assets		28	12	0
Water Rights Write-Off		19	6	10
Other		10	9	14
Other Expenses		$ 57	$ 79	$ 24
[1]	During the fourth quarter of 2016, we recognized a full allowance on a non-trade receivable in the MCAC SBU as a result of payment delays and discussions with the counterparty. The allowance relates to certain reimbursements the Company was expecting in connection with a legal matter. Management believes the counterparty is obligated to pay and plans to continue to attempt to fully collect the non-trade receivable.

Asset Impairment Expense (Impai

Asset Impairment Expense (Impairment of Long-Lived Assets Held and Used by Asset) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Asset impairment expense	$ 537	$ 1,096	$ 285
Impairment of Long-Lived Assets Held-for-use	537	1,096	285
DPL Subsidiary [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	175	859	0
Laurel Mountain [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	121	0	0
Kazakhstan Hydro [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets to be Disposed of	92	0	0
Kazakhstan [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets to be Disposed of	94	0	0
Kilroot [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	37	0	121
buffalo gap III [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	0	0	116
UK Wind (Newfield) [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	0		37
UK Wind Development Projects [Domain]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use		0	37
buffalo gap II [Member] [Member]
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	0	159	0
Buffalo Gap I
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	0	77	0
Other
Debt Instrument [Line Items]
Impairment of Long-Lived Assets Held-for-use	$ 18	$ 1	$ 11

Asset Impairment Expense (Narra

Asset Impairment Expense (Narrative) (Details) $ in Millions

2 Months Ended

3 Months Ended

6 Months Ended

8 Months Ended

9 Months Ended

12 Months Ended

Feb. 28, 2017USD ($)

Jun. 30, 2017USD ($)

Mar. 31, 2016USD ($)

Jun. 30, 2016USD ($)

Aug. 31, 2016USD ($)

Sep. 30, 2016USD ($)

Dec. 31, 2017USD ($)

Dec. 31, 2016USD ($)project

Dec. 31, 2015USD ($)

Mar. 31, 2017USD ($)

Jun. 30, 2015project

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

$ 537

$ 1,096

$ 285

Other Asset Impairment Charges

537

1,096

285

Laurel Mountain [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

121

0

0

Kazakhstan Hydro [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets to be Disposed of

92

0

0

Kazakhstan [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets to be Disposed of

94

0

0

Buffalo Gap I

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

0

77

0

DPL Subsidiary [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

175

859

0

buffalo gap II [Member] [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

0

159

0

Kilroot [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

37

0

121

UK Wind (Newfield) [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

0

37

buffalo gap III [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

0

0

116

UK Wind Development Projects [Domain]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

$ 0

37

Assets, fair value

1

Assets carrying amount

38

number of projects no longer being pursued | project

2

number of impaired projects | project

4

Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Kazakhstan Hydro [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets to be Disposed of

92

Assets carrying amount

$ 190

Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses)

100

Fair Value Less Costs To Sell

$ 92

Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Kazakhstan [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets to be Disposed of

94

Assets carrying amount

$ 171

Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses)

92

Fair Value Less Costs To Sell

$ 29

Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | DPL Peaking Generation [Domain]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets to be Disposed of

109

Assets carrying amount

346

Fair Value Less Costs To Sell

237

Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | DPL Subsidiary [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets to be Disposed of

66

Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Stuart Station [Member]

Debt Instrument [Line Items]

Assets, fair value

3

Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Killen Station [Member]

Debt Instrument [Line Items]

Assets, fair value

8

Long Lived Assets Held And Used [Member] | Parent Company [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

$ 49

$ 23

Long Lived Assets Held And Used [Member] | Laurel Mountain [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

121

Assets, fair value

33

Other Asset Impairment Charges

[1]

121

Long Lived Assets Held And Used [Member] | Buffalo Gap I

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

$ 77

Assets, fair value

36

Other Asset Impairment Charges

[1]

$ 77

Long Lived Assets Held And Used [Member] | Miami Fort [Domain]

Debt Instrument [Line Items]

Assets, fair value

36

Long Lived Assets Held And Used [Member] | Zimmer Station [Member]

Debt Instrument [Line Items]

Assets, fair value

24

Long Lived Assets Held And Used [Member] | DPL Peaking Generation [Domain]

Debt Instrument [Line Items]

Assets, fair value

$ 5

2

Long Lived Assets Held And Used [Member] | DPL Subsidiary [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

235

624

Other Asset Impairment Charges

[1]

$ 66

235

624

Long Lived Assets Held And Used [Member] | buffalo gap II [Member] [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

159

Assets, fair value

92

Other Asset Impairment Charges

[1]

$ 159

Long Lived Assets Held And Used [Member] | Stuart Station [Member]

Debt Instrument [Line Items]

Assets, fair value

57

Long Lived Assets Held And Used [Member] | Killen Station [Member]

Debt Instrument [Line Items]

Assets, fair value

$ 84

43

Long Lived Assets Held And Used [Member] | Kilroot [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

37

121

Assets, fair value

20

70

Other Asset Impairment Charges

[1]

$ 37

Long Lived Assets Held And Used [Member] | Conesville DP&L

Debt Instrument [Line Items]

Assets, fair value

$ 1

Long Lived Assets Held And Used [Member] | buffalo gap III [Member]

Debt Instrument [Line Items]

Impairment of Long-Lived Assets Held-for-use

116

Assets, fair value

$ 118

[1]

See Note 19—Asset Impairment Expense for further information.

Income Taxes (Components of Inc

Income Taxes (Components of Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Federal:
Current	$ 0	$ 2	$ 9
Deferred	545	(361)	(63)
State:
Current	0	1	1
Deferred	1	(4)	(5)
Foreign:
Current	335	318	470
Deferred	109	76	0
Total	$ 990	$ 32	$ 412

Income Taxes (Effective Income

Income Taxes (Effective Income Tax Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory Federal tax rate	35.00%	35.00%	35.00%
State taxes, net of Federal tax benefit	(7.00%)	(18.00%)	(6.00%)
Taxes on foreign earnings	(0.00%)	46.00%	(5.00%)
Valuation allowance	10.00%	10.00%	(5.00%)
Uncertain tax positions	0.00%	4.00%	(1.00%)
Noncontrolling Interest on Buffalo Gap impairments	0.00%	31.00%	3.00%
Change in tax law	90.00%	12.00%	0.00%
Goodwill impairment	0.00%	0.00%	11.00%
Other—net	0.00%	(11.00%)	0.00%
Effective tax rate	128.00%	17.00%	42.00%

Income Taxes (Income Tax Payabl

Income Taxes (Income Tax Payables and Income Tax Receivables) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income taxes receivable—current	$ 147	$ 136
Total income taxes receivable	147	136
Income taxes payable—current	129	149
Income taxes payable—noncurrent	17	22
Total income taxes payable	$ 146	$ 171

Income Taxes (Deferred Tax Asse

Income Taxes (Deferred Tax Assets and Deferred Tax Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred Tax Liabilities:
Differences between book and tax basis of property	$ (1,424)	$ (1,926)
Other taxable temporary differences	(143)	(335)
Deferred Tax Liabilities, Gross	1,567	2,261
Deferred Tax Assets:
Operating loss carryforwards	1,439	2,088
Capital loss carryforwards	63	59
Bad debt and other book provisions	66	96
Tax credit carryforwards	51	54
Other deductible temporary differences	60	263
Total gross deferred tax asset	1,679	2,560
Less: valuation allowance	(988)	(876)
Total net deferred tax asset	691	1,684
Total deferred tax liability	$ (876)	$ (577)

Income Taxes (Income (Loss) fro

Income Taxes (Income (Loss) from Continuing Operations Before Income Tax) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
U.S.	$ (511)	$ (1,305)	$ (612)
Non-U.S.	1,282	1,492	1,601
INCOME FROM CONTINUING OPERATIONS BEFORE TAXES AND EQUITY IN EARNINGS OF AFFILIATES	$ 771	$ 187	$ 989

Income Taxes (Unrecognized Tax

Income Taxes (Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits, Interest on Income Taxes Expense	$ (1)	$ (2)	$ (2)
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	7	6
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	352	364	384
Additions for current year tax positions	0	2	2
Additions for tax positions of prior years	2	1	12
Reductions for tax positions of prior years	(5)	(1)	(7)
Effects of foreign currency translation	0	0	(3)
Settlements	0	(13)	(17)
Lapse of statute of limitations	(1)	(1)	(7)
Ending balance	348	352	364
Unrecognized Tax Benefits, Income Tax Penalties Accrued	0	0
Unrecognized Tax Benefits, Income Tax Penalties Expense	$ 0	$ 0	$ 0

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent			90.00%	12.00%	0.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			10.00%	10.00%	(5.00%)
Effective Income Tax Rate Reconciliation Withholding Tax Reversals			0.00%	31.00%	3.00%
Deferred Tax Liabilities, Undistributed Foreign Earnings			$ 0
Undistributed Earnings of Foreign Subsidiaries			$ 4,000,000,000
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent			0.00%	(46.00%)	5.00%
Effective tax rate			128.00%	17.00%	42.00%
Increase (decrease) in valuation allowance			$ (112,000,000)	$ (18,000,000)
Valuation allowance			988,000,000	876,000,000
Tax benefits related to tax status of operations in countries subject to reduced tax rates			26,000,000	20,000,000	$ 21,000,000
Income tax expense			$ (990,000,000)	$ (32,000,000)	$ (412,000,000)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%	35.00%	35.00%
Tax benefits related to tax status of operations in countries subject to reduced tax rates per share (in dollars per share)			$ 0.03	$ 0.02	$ 0.02
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued:
Interest on income taxes accrued			$ 7,000,000	$ 6,000,000
Unrecognized Tax Benefits, Income Tax Penalties Accrued			0	0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense:
Unrecognized Tax Benefits, Interest on Income Taxes Expense			1,000,000	2,000,000	$ 2,000,000
Unrecognized Tax Benefits, Income Tax Penalties Expense			0	0	0
Uncertain Tax Positions Additional Disclosures:
Unrecognized tax benefits			348,000,000	352,000,000	364,000,000	$ 384,000,000
Unrecognized tax benefits that would impact effective tax rate			332,000,000	332,000,000	343,000,000
Unrecognized tax benefits that would impact effective tax rate portion with attributes warranting full valuation allowance			29,000,000	24,000,000	24,000,000
Unrecognized Tax benefits Anticipated To Result In Ne Decrease of Unrecognized Tax Benefits WIthin 12 Months of Balance Sheet Date Minimum			5,000,000
Unrecognized tax benefits anticipated to result in net decrease of unrecognized tax benefits within 12 months, maximum			15,000,000
Federal
Income Tax Disclosures [Line Items]
Operating loss carryforwards			1,900,000,000
State and Local Jurisdiction
Income Tax Disclosures [Line Items]
Operating loss carryforwards			9,300,000,000
Foreign Tax Authority
Income Tax Disclosures [Line Items]
Operating loss carryforwards			2,800,000,000
General Business Tax Credit Carryforward
Income Tax Disclosures [Line Items]
Tax credit carryforward			21,000,000
Federal Alternative Minimum Tax
Income Tax Disclosures [Line Items]
Tax credit carryforward			5,000,000
Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward			28,000,000
2021 Expiration | Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward			18,000,000
Year 2023 to 2028 [Member] | Foreign Jurisdictions
Income Tax Disclosures [Line Items]
Tax credit carryforward			1,000,000
No Expiration
Income Tax Disclosures [Line Items]
Tax credit carryforward			9,000,000
VIET NAM
Income Tax Disclosures [Line Items]
Income tax expense			$ (13,000,000)	$ (15,000,000)	$ (8,000,000)
Tax benefits related to tax status of operations in countries subject to reduced tax rates per share (in dollars per share)				$ 0.01	$ 0.01
Chilean tax reform Member [Member]
Income Tax Disclosures [Line Items]
Effective tax rate	25.00%		25.50%
Other Tax Expense (Benefit)	$ 26,000,000
Subsequent Event [Member] | Chilean tax reform Member [Member]
Income Tax Disclosures [Line Items]
Effective tax rate		27.00%
UNITED STATES
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent			88.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			5.00%
Income tax expense			$ (714,000,000)
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 39,000,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount			$ 675,000,000
ARGENTINA
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Percent			3.00%
Effective tax rate			35.00%
Income tax expense			$ 0
ARGENTINA | FY 2018 - 2019 [Member]
Income Tax Disclosures [Line Items]
Effective tax rate			30.00%
ARGENTINA | FY 2020 and beyond [Member]
Income Tax Disclosures [Line Items]
Effective tax rate			25.00%
Cash, Restricted Cash, Unbilled Receivables, and Other Liquid Assets [Member] | UNITED STATES
Income Tax Disclosures [Line Items]
Effective tax rate			15.50%
Non-cash [Member] | UNITED STATES
Income Tax Disclosures [Line Items]
Effective tax rate			8.00%

Discontinued Operations and 160

Discontinued Operations and Held-For-Sale Businesses (Schedule of Disposal Groups, Including Discontinued Operations) (Details) - USD ($)		Oct. 31, 2016	Jun. 30, 2016	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Dec. 31, 2017		Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Allowance for Doubtful Accounts									$ 94,000,000							$ 94,000,000
Cash Provided by (Used in) Operating Activities, Discontinued Operations														$ 164,000,000		529,000,000	$ (125,000,000)
Disposal Group, Including Discontinued Operation, Revenue														3,320,000,000		4,036,000,000	4,430,000,000
Income tax expense														21,000,000		(229,000,000)	53,000,000
Income (loss) from operations of discontinued businesses, after income tax														(18,000,000)		151,000,000	80,000,000
Net loss from disposal and impairments of discontinued businesses, after income tax														(611,000,000)		(1,119,000,000)	0
Disposal Group, Including Discontinued Operation, Assets	[1]			$ 2,034,000,000					4,936,000,000					2,034,000,000		4,936,000,000
Disposal Group, Including Discontinued Operation, Liabilities	[1]			1,033,000,000					4,249,000,000					1,033,000,000		4,249,000,000
Disposal Group, Including Discontinued Operation, Costs of Goods Sold														(3,151,000,000)		(3,954,000,000)	(4,227,000,000)
Impairment Expense Pre Tax Total				(277,000,000)		$ (2,000,000)	$ (90,000,000)	$ (168,000,000)	(623,000,000)	$ (79,000,000)	$ (235,000,000)	$ (159,000,000)
Disposal Group, Including Discontinued Operation, Other Expense														(166,000,000)		(160,000,000)	(70,000,000)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax														(608,000,000)		(1,463,000,000)	133,000,000
Discontinued Operation, Tax Effect of Discontinued Operation														21,000,000		(495,000,000)	53,000,000
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent														(654,000,000)		(1,110,000,000)	(12,000,000)
Cash Provided by (Used in) Investing Activities, Discontinued Operations														(288,000,000)		(368,000,000)	(65,000,000)
Asset Impairment Charges														537,000,000		1,098,000,000	602,000,000
Other Asset Impairment Charges														537,000,000		1,096,000,000	285,000,000
Eletropaulo Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents				0					61,000,000					0		61,000,000
Disposal Group, Including Discontinued Operation, Prepaid and Other Assets				0					268,000,000					0		268,000,000
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net				0					745,000,000					0		745,000,000
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment				0					2,504,000,000					0		2,504,000,000
Disposal Group, Including Discontinued Operations, Investments in and Advances to Affiliates				86,000,000	[2]				0					86,000,000	[2]	0
Disposal Group, Including Discontinued Operation, Deferred Tax Assets				0					554,000,000					0		554,000,000
Disposal Group, Including Discontinued Operation, Other Assets				0					305,000,000					0		305,000,000
Disposal Group, Including Discontinued Operation, Accounts Payable				0					418,000,000					0		418,000,000
Disposal Group, Including Discontinued Operation, Accrued Liabilities				0					954,000,000					0		954,000,000
Non Recourse Debt Held For Sale Or Discontinued Operations				0					1,009,000,000					0		1,009,000,000
Disposal Group, Including Discontinued Operation, Other Liabilities				0					31,000,000					0		31,000,000
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax														(633,000,000)		(192,000,000)	73,000,000
Sul Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net loss from disposal and impairments of discontinued businesses, after income tax		$ (737,000,000)	$ (382,000,000)													(1,119,000,000)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax																(1,413,000,000)	$ (32,000,000)
Discontinued Operations [Member] | Eletropaulo Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Assets				86,000,000					4,936,000,000					86,000,000		4,936,000,000
Disposal Group, Including Discontinued Operation, Liabilities				0					4,249,000,000					0		4,249,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Assets				1,948,000,000	[3]				0					1,948,000,000	[3]	0
Disposal Group, Including Discontinued Operation, Liabilities				$ 1,033,000,000	[3]				$ 0					$ 1,033,000,000	[3]	$ 0
Discontinued Operations, Held-for-sale [Member] | Sul Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Other Asset Impairment Charges	[4]												$ 783,000,000
[1]	Amounts at December 31, 2016 are classified as both current and long-term on the Consolidated Balance Sheet.
[2]	Represents the Company's 17% ownership interest in Eletropaulo
[3]	Masinloc, Eletrica Santiago, and the DPL peaker assets were classified as held-for-sale as of December 31, 2017. See Note 22—Held-for-Sale Businesses and Dispositions for further information.
[4]	See Note 19—Asset Impairment Expense for further information.

Discontinued Operations and 161

Discontinued Operations and Held-For-Sale Businesses (Narrative) (Details) - USD ($)	Oct. 31, 2016	Mar. 31, 2015	Dec. 31, 2017	Nov. 30, 2017	Jun. 30, 2016	Jun. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Equity Method Investment Retained after Disposal, Ownership Interest after Disposal			17.00%
Cash Provided by (Used in) Operating Activities, Discontinued Operations							$ 164,000,000	$ 529,000,000	$ (125,000,000)
Cash Provided by (Used in) Investing Activities, Discontinued Operations							(288,000,000)	(368,000,000)	(65,000,000)
Disposal Group, Including Discontinued Operation, Revenue							3,320,000,000	4,036,000,000	4,430,000,000
Disposal Group, Including Discontinued Operation, Costs of Goods Sold							3,151,000,000	3,954,000,000	4,227,000,000
Asset Impairment Charges							537,000,000	1,098,000,000	602,000,000
Net loss from disposal and impairments of discontinued operations							611,000,000	1,119,000,000	0
Other Asset Impairment Charges							537,000,000	1,096,000,000	285,000,000
Income (Loss) from Continuing Operations Attributable to Parent							(507,000,000)	(20,000,000)	318,000,000
Impairment Expense Pre Tax Total							(611,000,000)	(1,385,000,000)	0
Disposal Group, Including Discontinued Operation, Other Expense							(166,000,000)	(160,000,000)	(70,000,000)
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax							3,000,000	(78,000,000)	133,000,000
Disposal Group, Including Discontinued Operation, Assets, Noncurrent			$ 0				0	3,343,000,000
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax							(608,000,000)	(1,463,000,000)	133,000,000
Income (loss) on discontinued operations, before tax, attributable to Noncontrolling interest							(25,000,000)	(142,000,000)	(92,000,000)
Income (loss) from discontinued operations, before income tax, attributable to parent							(633,000,000)	(1,605,000,000)	41,000,000
Disposal Group, Including Discontinued Operation, Liabilities								94,000,000
Discontinued Operation, Tax Effect of Discontinued Operation							(21,000,000)	495,000,000	(53,000,000)
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent							(654,000,000)	(1,110,000,000)	(12,000,000)
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Armenia Mountain
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sale Agreement, Buyer Option To Purchase Ownership Interest, Sales Price		$ 75,000,000
Eletropaulo Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deconsolidation, Gain (Loss), Amount				$ 611,000,000
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents			0				0	61,000,000
Disposal Group, Including Discontinued Operation, Accrued Liabilities			0				0	954,000,000
Disposal Group, Including Discontinued Operation, Deferred Tax Assets			0				0	554,000,000
Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses)							(455,000,000)
Disposal Group, Including Discontinued Operation, Pension Gains (Losses)							(243,000,000)
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax							(633,000,000)	(192,000,000)	73,000,000
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net			0				0	745,000,000
Disposal Group, Including Discontinued Operation, Other Assets, Current			0				0	499,000,000
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment			0				0	2,504,000,000
Disposal Group, Including Discontinued Operation, Other Assets			0				0	305,000,000
Disposal Group, Including Discontinued Operation, Accounts Payable			0				0	418,000,000
Debt excluded from non-recourse debt and included in current and noncurrent liabilities of held for sale and discontinued businesses			0				0	1,009,000,000
Disposal Group, Including Discontinued Operation, Pension Plan Benefit Obligation, Noncurrent			0				0	1,159,000,000
Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent			0				0	678,000,000
Disposal Group, Including Discontinued Operation, Other Liabilities			$ 0				$ 0	31,000,000
Sul Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net loss from disposal and impairments of discontinued operations	$ 737,000,000				$ 382,000,000			1,119,000,000
Disposal Group, Including Discontinued Operation, Foreign Currency Translation Gains (Losses)								(1,000,000,000)
Reduction in Stockholders equity due to sale of business								92,000,000
Impairment Expense Pre Tax Total						$ 602,000,000
Discontinued Operation, Tax (Expense) Benefit from Provision for (Gain) Loss on Disposal					266,000,000
Disposal Group, Including Discontinued Operation, Assets, Noncurrent					1,600,000,000	$ 1,600,000,000
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax								$ (1,413,000,000)	$ (32,000,000)
Sul Subsidiary [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Tax (Expense) Benefit from Provision for (Gain) Loss on Disposal					$ 135,000,000
Proceeds from Divestiture of Businesses, Net of Cash Divested	$ 484,000,000

Acquisitions and Dispositions (

Acquisitions and Dispositions (Details) - USD ($) $ in Millions	Apr. 07, 2017	Jan. 27, 2016	Jan. 01, 2016	Mar. 31, 2015	Jun. 25, 2014	Jun. 30, 2016	Sep. 30, 2015	Dec. 31, 2017	Dec. 31, 2016	Sep. 16, 2016	Dec. 31, 2015	Dec. 17, 2017	Jun. 30, 2017
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business								$ (52)	$ 29		$ 29
Proceeds from Divestiture of Businesses and Interests in Affiliates								108	631		138
Income (Loss) from Continuing Operations Attributable to Parent								(507)	(20)		318
Dispositions and Held-for-Sales Businesses
Proceeds from Sale of Ownership Interests								94	0		154
Masinloc Subsidiary [Member]
Dispositions and Held-for-Sales Businesses
Sale of Stock, Consideration Received on Transaction					$ 436
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								129	134		133
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Electrica Santiago (Gener ESSA) [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								9	11		10
Proceeds from Divestiture of Businesses and Interests in Affiliates								300
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | DPL Peaking Generation [Domain]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								17	20		24
Proceeds from Divestiture of Businesses and Interests in Affiliates								241
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Masinloc Subsidiary [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								103	103		99
Proceeds from Divestiture of Businesses and Interests in Affiliates								1,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								72	32		91
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Zimmer and Miami Fort [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								26	(14)		6
Gain (Loss) on Disposition of Business								13
Proceeds from Divestiture of Businesses and Interests in Affiliates								70
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Kazakhstan Hydro [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								33	34		52
Gain (Loss) on Disposition of Business								(33)
Proceeds from Divestiture of Businesses and Interests in Affiliates								75
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Armenia Mountain [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								0	0		6
Gain (Loss) on Disposition of Business							$ 22
Proceeds from Divestiture of Businesses and Interests in Affiliates							$ 64
Dispositions and Held-for-Sales Businesses
Ownership interest sold				100.00%
Sale Agreement, Buyer Option To Purchase Ownership Interest, Sales Price				$ 75
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | UK Wind Projects
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business						$ (20)
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Kelanitissa [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business		$ 5
Proceeds from Divestiture of Businesses and Interests in Affiliates		$ 18
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Kazakhstan [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								13	12		16
Gain (Loss) on Disposition of Business	$ (49)
Proceeds from Divestiture of Businesses and Interests in Affiliates	$ 24
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | DPLER [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax								$ 0	0		11
Gain (Loss) on Disposition of Business			$ 49
Proceeds from Divestiture of Businesses and Interests in Affiliates			$ 76
Masinloc Subsidiary [Member]
Dispositions and Held-for-Sales Businesses
Ownership interest sold					45.00%			100.00%				51.00%
Divestiture of Businesses, Portion Contingent Upon Achievement of Certain Restructuring Efficiencies					$ 23
Kazakhstan Hydro [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of Long-Lived Assets to be Disposed of								$ 92	0		$ 0
Distributed energy [Domain]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Business Combination, Consideration Transferred										$ 43
UK Wind Projects
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Gain (Loss) on Disposition of Business									$ (20)
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Masinloc Subsidiary [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Assets Carrying Amount Disclosure Nonrecurring								475
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | DPL Peaking Generation [Domain]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of Long-Lived Assets to be Disposed of								109
Fair Value Less Costs To Sell								237
Assets Carrying Amount Disclosure Nonrecurring								346
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Electrica Santiago (Gener ESSA) [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Assets Carrying Amount Disclosure Nonrecurring								186
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Kazakhstan Hydro [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of Long-Lived Assets to be Disposed of								$ 92
Fair Value Less Costs To Sell													$ 92
Assets Carrying Amount Disclosure Nonrecurring													$ 190

Acquisitions Acquistions (Detai

Acquisitions Acquistions (Details) - USD ($) $ in Millions	Feb. 18, 2015	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Sep. 16, 2016	Aug. 03, 2017
Alto Sertao II [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired						100.00%
Business Combination, Contract Purchase Price						$ 181
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities						348
Business Combination, Contingent Consideration, Liability						$ 30
Payments to Acquire Businesses, Net of Cash Acquired		$ 143
Bauru Solar Complex [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired			$ 55
Other Payments to Acquire Businesses			$ 140
Project Financing Disbursed				$ 45
Main street power [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Business Combination, Consideration Transferred	$ 25
Payments to Acquire Businesses, Gross	$ 20
Distributed energy [Domain]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred					$ 43

Earnings Per Share (Schedule of

Earnings Per Share (Schedule of Earnings Per Share, Basic and Diluted) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016		Dec. 31, 2015
Class of Stock [Line Items]
Income (loss) from continuing operations, after Adjustment to Retained Earnings, Basic Earnings									$ (507)	$ (25)	[1]	$ 318
Weighted Average Number of Shares Outstanding, Basic (in shares)									660	660		687
Income (Loss) from Continuing Operations, Per Basic Share	$ (1.03)	$ 0.22	$ 0.08	$ 0.04	$ (0.35)	$ 0.26	$ (0.15)	$ 0.21	$ (0.77)	$ (0.04)		$ 0.46
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements (in shares)									0	0		2
Weighted Average Number of Shares Outstanding, Diluted (in shares)									660	660		689
Income (Loss) from Continuing Operations, Per Diluted Share	$ (1.03)	$ 0.22	$ 0.08	$ 0.04	$ (0.35)	$ 0.26	$ (0.15)	$ 0.20	$ (0.77)	$ (0.04)		$ 0.46
Income (loss) from continuing operations, after Adjustment to Retained Earnings, Diluted Earnings									$ (507)	$ (25)		$ 318
Temporary Equity, Accretion to Redemption Value									$ 25	$ 4
Restricted Stock Units (RSUs) [Member]
Class of Stock [Line Items]
Income (Loss) from Continuing Operations, Per Diluted Share									$ 0	$ 0		$ 0
Restricted Stock Units (RSUs) [Member]
Class of Stock [Line Items]
Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units									$ 0	$ 0		$ 0
DPL Subsidiary [Member]
Class of Stock [Line Items]
Temporary Equity, Accretion to Redemption Value										$ 5
[1]	Loss from continuing operations, net of tax, of $20 million less the $5 million adjustment to retained earnings to record the DP&L redeemable preferred stock at its redemption value as of December 31, 2016.

Earnings Per Share (Narrative)

Earnings Per Share (Narrative) (Details) - $ / shares shares in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Income (Loss) from Continuing Operations, Per Basic Share	$ (1.03)	$ 0.22	$ 0.08	$ 0.04	$ (0.35)	$ 0.26	$ (0.15)	$ 0.21	$ (0.77)	$ (0.04)	$ 0.46
Antidilutive securities excluded from computation of earnings per share									7	8	8
Earnings Per Share, Basic	$ (2.03)	$ 0.23	$ 0.08	$ 0.04	$ (1.44)	$ 0.26	$ (0.73)	$ 0.19	$ (1.76)	$ (1.72)	$ 0.45
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share										15	15

Risks And Uncertainties (Detail

Risks And Uncertainties (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)businesssegmentcustomerRate	Dec. 31, 2016USD ($)customer	Jan. 01, 2016USD ($)	Dec. 31, 2015USD ($)customer	Jan. 01, 2015USD ($)
Unusual Risk or Uncertainty [Line Items]
Number of SBUs | business	5
Number of strategic business units | segment	5
Segment Reporting, Additional Information about Entity's Reportable Segments | business	2
Cash and cash equivalents	$ 949	$ 1,244	$ 1,218	$ 1,218	$ 1,449
Percent of revenue generated outside US	69.00%
Investment in and advances to subsidiaries and affiliates	$ 1,197	$ 621		$ 610
Debt Default Amount	$ 1,019
Number of customers that accounted for 10% of more of total revenue | customer	0	0		0
Percentage of total revenues from a single customer (less than)	10.00%
AES llumina [Member]
Unusual Risk or Uncertainty [Line Items]
Loss from Catastrophes	$ 2
Availability to generate electricity | Rate	75.00%
Alto Maipo [Member]
Unusual Risk or Uncertainty [Line Items]
Derivative Liabililty, Amount in Technical Default	$ 132
Project Completion Percentage	61.00%
Assets Carrying Amount Disclosure Nonrecurring	$ 1,400
Deferred Tax Assets, Net	60
Project Budgeted Cost	$ 2,000
Investment In Affiliate Ownership Percentage	62.00%
Gener Subsidiary [Member]
Unusual Risk or Uncertainty [Line Items]
Investment In Affiliate Ownership Percentage	67.00%
AES Puerto Rico [Member] | Covenant Violation [Member]
Unusual Risk or Uncertainty [Line Items]
Debt Instrument, Debt Default, Amount	$ 365
Debt Default Amount	365
Alto Maipo [Member] | Covenant Violation [Member]
Unusual Risk or Uncertainty [Line Items]
Debt Instrument, Debt Default, Amount	618
AES llumina [Member] | Covenant Violation [Member]
Unusual Risk or Uncertainty [Line Items]
Debt Default Amount	36
AES Puerto Rico [Member]
Unusual Risk or Uncertainty [Line Items]
Assets Carrying Amount Disclosure Nonrecurring	627
Accounts Receivable, Gross, Current	86
Accounts Receivable, Past Due	$ 53

Related Party Transactions (Sch

Related Party Transactions (Schedule of related Party Transactions) (Details) - Affiliated Entity - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Interest Income	$ 8	$ 4	$ 25
Interest expense	36	39	33
Electricity Generation Plant, Non-Nuclear [Member]
Related Party Transaction [Line Items]
Revenue—Non-Regulated	1,297	1,100	1,099
Cost of Sales—Non-Regulated	$ 220	$ 210	$ 330

Related Party Transactions (168

Related Party Transactions (Schedule of Related Party Receivables Payables) (Details) - Affiliated Entity - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Receivables from Related Parties	$ 250	$ 218
Accounts and notes payable to related parties	$ 727	$ 892

Selected Quarterly Financial169

Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 08, 2017	Dec. 31, 2017		Sep. 30, 2017		Jun. 30, 2017		Mar. 31, 2017		Dec. 31, 2016		Sep. 30, 2016		Jun. 30, 2016		Mar. 31, 2016		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues		$ 2,643		$ 2,693		$ 2,613		$ 2,581		$ 2,660		$ 2,639		$ 2,452		$ 2,530		$ 10,530	$ 10,281	$ 11,260
Selected Quarterly Financial Information [Abstract]
Operating margin		643		642		625		554		632		691		556		501		2,464	2,380	2,663
Income (loss) from continuing operations, net of tax		(622)	[1]	236	[1]	141	[1]	97	[1]	(136)	[2]	238	[2]	2	[2]	87	[2]	(148)	191	682
Income (loss) from discontinued operations, net of tax		(664)		25		9		1		(557)		(9)		(389)		(13)
NET INCOME (LOSS)		(1,286)		261		150		98		(693)		229		(387)		74		(777)	(777)	762
Net income (loss) attributable to The AES Corporation		$ (1,342)		$ 152		$ 53		$ (24)		$ (949)		$ 175		$ (482)		$ 126		$ (1,161)	$ (1,130)	$ 306
Basic income (loss) per share:
Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax		$ (1.03)		$ 0.22		$ 0.08		$ 0.04		$ (0.35)		$ 0.26		$ (0.15)		$ 0.21		$ (0.77)	$ (0.04)	$ 0.46
Income (loss) from discontinued operations attributable to The AES Corporation common stockholders, net of tax		(1)		0.01		0		0		(1.09)		0		(0.58)		(0.02)		(0.99)	(1.68)	(0.01)
NET INCOME ATTRIBUTABLE TO THE AES CORPORATION COMMON STOCKHOLDERS		(2.03)		0.23		0.08		0.04		(1.44)		0.26		(0.73)		0.19		(1.76)	(1.72)	0.45
Diluted income (loss) per share:
Income (loss) from continuing operations attributable to The AES Corporation common stockholders, net of tax		(1.03)		0.22		0.08		0.04		(0.35)		0.26		(0.15)		0.20		(0.77)	(0.04)	0.46
Loss from discontinued operations attributable to The AES Corporation common stockholders, net of tax		(1)		0.01		0		0		(1.09)		0		(0.58)		(0.01)		(0.99)	(1.68)	(0.02)
NET INCOME ATTRIBUTABLE TO THE AES CORPORATION COMMON STOCKHOLDERS		(2.03)		0.23		0.08		0.04		(1.44)		0.26		(0.73)		0.19		(1.76)	(1.72)	0.44
Dividends declared per common share	$ 0.13	$ 0.25		$ 0.12		$ 0		$ 0.12		$ 0.23		$ 0.11		$ 0		$ 0.11		$ 0.49	$ 0.45	$ 0.41
Impairment expense pre-tax total		$ 277		$ 2		$ 90		$ 168		$ 623		$ 79		$ 235		$ 159
Net equity in earnings of affiliates																		$ (71)	$ (36)	$ (105)
[1]	Includes pre-tax impairment expense of $168 million, $90 million, $2 million and $277 million, for the first, second, third and fourth quarters of 2017, respectively. See Note 19—Asset Impairment Expense for further discussion.
[2]	Includes pre-tax impairment expense of $159 million, $235 million, $79 million and $623 million, for the first, second, third and fourth quarters of 2016, respectively. See Note 19—Asset Impairment Expense for further discussion.

Subsequent Event Subsequent 170

Subsequent Event Subsequent Events (Details)	Jan. 01, 2018
Fluence [Member] | Subsequent Event
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	50.00%

Schedule I - Condensed Finan171

Schedule I - Condensed Financial Information of Parent (Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2016	Dec. 31, 2015	Jan. 01, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 949	$ 1,244	$ 1,218	$ 1,218	$ 1,449
Restricted cash	274	277
Total current assets	6,398	6,416
Investment in and advances to subsidiaries and affiliates	1,197	621		610
Office Equipment:
Cost	24,119	24,911
Accumulated depreciation	(7,942)	(7,919)
Property, plant and equipment, net	20,296	20,415
Other Assets:
Deferred income taxes	130	227
Other assets	1,741	1,775
Total other assets	6,418	9,293
TOTAL ASSETS	33,112	36,124		36,545
Current Liabilities:
Accounts payable	1,371	1,238
Accrued and other liabilities	1,232	1,117
Total current liabilities	6,028	5,277
Long-term Liabilities:
Other long-term liabilities	2,365	2,327
Total noncurrent liabilities	21,402	24,365
Stockholders' equity:
Common stock	8	8
Additional paid-in capital	8,501	8,592
Accumulated deficit	(2,276)	(1,146)
Accumulated other comprehensive loss	(1,876)	(2,756)		(3,883)
Treasury stock	(1,892)	(1,904)
Total AES Corporation stockholders’ equity	2,465	2,794
TOTAL LIABILITIES AND EQUITY	33,112	36,124
Parent Company [Member]
Current Assets:
Cash and cash equivalents	10	109		$ 186		$ 511
Restricted cash	0	3
Accounts and notes receivable from subsidiaries	143	155
Prepaid expenses and other current assets	27	39
Total current assets	180	306
Investment in and advances to subsidiaries and affiliates	8,239	7,561
Office Equipment:
Cost	27	26
Accumulated depreciation	(18)	(16)
Property, plant and equipment, net	9	10
Other Intangible Assets, Net	3	5
Other Assets:
Deferred financing costs, net of accumulated amortization of $2	5	5
Deferred income taxes	289	1,041
Other assets	2	13
Total other assets	299	1,064
TOTAL ASSETS	8,727	8,941
Current Liabilities:
Accounts payable	18	18
Accounts and notes payable to subsidiaries	381	304
Accrued and other liabilities	246	250
Senior notes payable—current portion	5	0
Total current liabilities	650	572
Long-term Liabilities:
Senior notes payable	4,625	4,154
Junior subordinated notes and debentures payable	0	517
Accounts and notes payable to subsidiaries	967	883
Other long-term liabilities	20	21
Total noncurrent liabilities	5,612	5,575
Stockholders' equity:
Common stock	8	8
Additional paid-in capital	8,501	8,592
Accumulated deficit	(2,276)	(1,146)
Accumulated other comprehensive loss	(1,876)	(2,756)
Treasury stock	(1,892)	(1,904)
Total AES Corporation stockholders’ equity	2,465	2,794
TOTAL LIABILITIES AND EQUITY	$ 8,727	$ 8,941

Schedule I - Condensed Finan172

Schedule I - Condensed Financial Information of Parent (Balance Sheet Parenthetical) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Parent Company
Condensed Financial Statements, Captions [Line Items]
Deferred financing costs, accumulated amortization	$ 2	$ 1

Schedule I - Condensed Finan173

Schedule I - Condensed Financial Information of Parent Schedule I - Condensed Financial Information of Parent (Statement of Operations) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Income Statements, Captions [Line Items]
Interest income									$ 244	$ 245	$ 256
General and administrative expenses									(215)	(194)	(196)
Other income									120	64	84
Other expense									(57)	(79)	(24)
Loss on extinguishment of debt									(68)	(13)	(182)
Interest expense									(1,170)	(1,134)	(1,145)
Income (loss) before income taxes									(521)	354	513
Income tax benefit (expense)									(990)	(32)	(412)
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION	$ (1,342)	$ 152	$ 53	$ (24)	$ (949)	$ 175	$ (482)	$ 126	(1,161)	(1,130)	306
Parent Company
Condensed Income Statements, Captions [Line Items]
Revenue from subsidiaries and affiliates									28	14	24
Equity in earnings of subsidiaries and affiliates									630	(615)	859
Interest income									49	19	24
General and administrative expenses									(158)	(144)	(154)
Other income									5	7	24
Other expense									(554)	(65)	(6)
Loss on extinguishment of debt									(92)	(14)	(105)
Interest expense									(317)	(344)	(364)
Income (loss) before income taxes									(409)	(1,142)	302
Income tax benefit (expense)									(752)	12	4
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION									$ (1,161)	$ (1,130)	$ 306

Schedule I - Condensed Finan174

Schedule I - Condensed Financial Information of Parent (Statement of Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION	$ (1,342)	$ 152	$ 53	$ (24)	$ (949)	$ 175	$ (482)	$ 126	$ (1,161)	$ (1,130)	$ 306
Foreign currency translation activity:
Foreign currency translation adjustments, net of income tax benefit (expense) of $11, $1 and $1, respectively									(9)	189	(1,019)
Reclassification to earnings, net of $0 income tax for all periods									643	992	0
Total foreign currency translation adjustments									634	1,181	(1,019)
Derivative activity:
Change in derivative fair value, net of income tax benefit (expense) of $13, $(5) and $4, respectively									(12)	5	(57)
Reclassification to earnings, net of income tax benefit (expense) of $1, $1 and $(12), respectively									50	37	66
Total change in fair value of derivatives									38	42	9
Pension activity:
Prior service cost for the period, net of income tax expense of $1, $5 and $0, respectively									2	11	1
Change in pension adjustments due to net actuarial gain (loss) for the period, net of income tax benefit (expense) of $6, $10 and $(7), respectively									(21)	(208)	60
Reclassification of earnings due to amortization of net actuarial loss, net of income tax benefit (expense) of $(126), $2 and $(2), respectively									266	10	16
Total pension adjustments									247	(187)	77
OTHER COMPREHENSIVE INCOME (LOSS)									919	1,036	(933)
COMPREHENSIVE INCOME (LOSS)									142	259	(171)
Parent Company
Condensed Financial Statements, Captions [Line Items]
NET INCOME (LOSS) ATTRIBUTABLE TO THE AES CORPORATION									(1,161)	(1,130)	306
Foreign currency translation activity:
Foreign currency translation adjustments, net of income tax benefit (expense) of $11, $1 and $1, respectively									18	117	(674)
Reclassification to earnings, net of $0 income tax for all periods									643	992	0
Total foreign currency translation adjustments									661	1,109	(674)
Derivative activity:
Change in derivative fair value, net of income tax benefit (expense) of $13, $(5) and $4, respectively									(14)	2	(5)
Reclassification to earnings, net of income tax benefit (expense) of $1, $1 and $(12), respectively									37	28	48
Total change in fair value of derivatives									23	30	43
Pension activity:
Prior service cost for the period, net of income tax expense of $1, $5 and $0, respectively									1	9	1
Change in pension adjustments due to net actuarial gain (loss) for the period, net of income tax benefit (expense) of $6, $10 and $(7), respectively									(20)	(22)	18
Reclassification of earnings due to amortization of net actuarial loss, net of income tax benefit (expense) of $(126), $2 and $(2), respectively									248	1	2
Total pension adjustments									229	(12)	21
OTHER COMPREHENSIVE INCOME (LOSS)									913	1,127	(610)
COMPREHENSIVE INCOME (LOSS)									$ (248)	$ (3)	$ (304)

Schedule I - Condensed Finan175

Schedule I - Condensed Financial Information of Parent (Statement of Comprehensive Income Parenthetical) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Foreign currency translation adjustments, income tax benefit (expense)	$ 17	$ 1	$ 1
Foreign currency, reclassification to earnings, income tax benefit (expense)	0	0	0
Change in derivative fair value, income tax benefit (expense)	10	(7)	16
Derivative reclassification to earnings, income tax benefit (expense)	(1)	(8)	(11)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Tax	1	6	0
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax	6	106	(29)
Pension, amortization of net actuarial loss, income tax benefit (expense)	(135)	(3)	(9)
Parent Company
Condensed Financial Statements, Captions [Line Items]
Foreign currency translation adjustments, income tax benefit (expense)	11	1	1
Foreign currency, reclassification to earnings, income tax benefit (expense)	0	0	0
Change in derivative fair value, income tax benefit (expense)	13	(5)	4
Derivative reclassification to earnings, income tax benefit (expense)	1	1	(12)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Tax	(1)	(5)	0
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax	6	10	(7)
Pension, amortization of net actuarial loss, income tax benefit (expense)	$ (126)	$ 2	$ (2)

Schedule I - Condensed Finan176

Schedule I - Condensed Financial Information of Parent (Statement of Cash Flows) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	$ 2,489	$ 2,884	$ 2,134
Investing Activities:
Decrease in restricted cash	(135)	(61)	(159)
Purchase of short term investments, net	(625)	(55)	(17)
Net cash used in investing activities	(2,749)	(2,108)	(2,366)
Financing Activities:
Borrowings under the revolver, net	2,156	1,465	959
Purchase of treasury stock	0	(79)	(482)
Common stock dividends paid	(317)	(290)	(276)
Payments for deferred financing costs	(100)	(105)	(90)
Payments to Noncontrolling Interests	(424)	(476)	(326)
Proceeds from (Payments for) Other Financing Activities	(52)	(44)	(7)
Net cash provided by (used in) financing activities	43	(747)	28
Effect of exchange rate changes on cash	3	9	(52)
Total increase (decrease) in cash and cash equivalents	(295)	26	(231)
Cash and cash equivalents, beginning	1,244	1,218
Cash and cash equivalents, ending	949	1,244	1,218
SUPPLEMENTAL DISCLOSURES:
Cash payments for interest, net of amounts capitalized	(1,196)	(1,273)	(1,265)
Cash payments for income taxes, net of refunds	(377)	(487)	(388)
Parent Company [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	148	818	475
Investing Activities:
Investment in and net advances to subsidiaries	(339)	(650)	(221)
Return of capital	243	247	501
Decrease in restricted cash	3	29	49
Additions to property, plant and equipment	(13)	(12)	(11)
Net cash used in investing activities	(106)	(386)	318
Financing Activities:
Borrowings under the revolver, net	207	0	0
Borrowings of notes payable and other coupon bearing securities	1,025	500	575
Repayments of notes payable and other coupon bearing securities	(1,353)	(808)	(915)
Loans from subsidiaries	309	183	0
Purchase of treasury stock	0	(79)	(482)
Proceeds from issuance of common stock	1	1	4
Common stock dividends paid	(317)	(290)	(276)
Payments for deferred financing costs	(12)	(12)	(6)
Payments to Noncontrolling Interests	0	(2)	0
Proceeds from (Payments for) Other Financing Activities	(7)	(3)	(18)
Net cash provided by (used in) financing activities	(147)	(510)	(1,118)
Effect of exchange rate changes on cash	6	1	0
Total increase (decrease) in cash and cash equivalents	(99)	(77)	(325)
Cash and cash equivalents, beginning	109	186	511
Cash and cash equivalents, ending	10	109	186
SUPPLEMENTAL DISCLOSURES:
Cash payments for interest, net of amounts capitalized	282	296	314
Cash payments for income taxes, net of refunds	$ 2	$ 6	$ 0

Schedule I - Condensed Finan177

Schedule I - Condensed Financial Information of Parent (Senior Notes and Junior Subordinated Notes) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ 4,630	$ 4,671
Less: Current maturities	(5)	0
Recourse Debt Non Current	4,625	$ 4,671
Unamortized (discounts)/premiums & debt issuance (costs)
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ (40)
Recourse Debt | Term Convertible Trust Securities 675 Due 2029 [Member]
Condensed Financial Statements, Captions [Line Items]
Interest Rate	6.75%	6.75%
Recourse Debt Total	$ 0	$ 517
Recourse Debt | 8.00% Senior Unsecured Note Due 2017
Condensed Financial Statements, Captions [Line Items]
Interest Rate		8.00%
Recourse Debt | 8.00% Senior Unsecured Note Due 2020
Condensed Financial Statements, Captions [Line Items]
Interest Rate	8.00%	8.00%
Recourse Debt | 7.38% Senior Unsecured Note Due 2021
Condensed Financial Statements, Captions [Line Items]
Interest Rate		7.38%
Recourse Debt | 5.50% Senior Unsecured Note Due 2024
Condensed Financial Statements, Captions [Line Items]
Interest Rate		5.50%
Recourse Debt | 5.50% Unsecured senior notes due 2025 [Domain]
Condensed Financial Statements, Captions [Line Items]
Interest Rate		5.50%
Recourse Debt | 6.00% senior notes due 2026 [Domain]
Condensed Financial Statements, Captions [Line Items]
Interest Rate		6.00%
Recourse Debt | LIBOR | Senior Secured Term Loan due 2022 [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate	2.00%	2.00%
Recourse Debt | LIBOR | Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate	2.00%	2.00%
Recourse Debt | LIBOR | Senior Unsecured Note LIBOR plus 3% due 2019
Condensed Financial Statements, Captions [Line Items]
Basis spread on variable rate	3.00%	3.00%
Parent Company
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ 4,630
Junior subordinated notes and debentures payable	0	$ 517
Parent Company | Unamortized (discounts)/premiums & debt issuance (costs)
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	(40)	(45)
Parent Company | Recourse Debt | Senior Secured Term Loan due 2022 [Member]
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ 521	0
Parent Company | Recourse Debt | 4.875% Senior Notes Due 2023 [Member] [Member]
Condensed Financial Statements, Captions [Line Items]
Interest Rate	4.88%
Recourse Debt Total	$ 713	713
Parent Company | Recourse Debt | Revolving Credit Facility [Member]
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ 207	$ 0
Parent Company | Recourse Debt | 8.00% Senior Unsecured Note Due 2017
Condensed Financial Statements, Captions [Line Items]
Interest Rate		8.00%
Parent Company | Recourse Debt | 8.00% Senior Unsecured Note Due 2020
Condensed Financial Statements, Captions [Line Items]
Interest Rate		8.00%
Parent Company | Recourse Debt | 7.38% Senior Unsecured Note Due 2021
Condensed Financial Statements, Captions [Line Items]
Interest Rate		7.38%
Parent Company | Recourse Debt | 5.50% Senior Unsecured Note Due 2024
Condensed Financial Statements, Captions [Line Items]
Interest Rate	5.50%	5.50%
Recourse Debt Total	$ 738	$ 738
Parent Company | Recourse Debt | 5.50% Unsecured senior notes due 2025 [Domain]
Condensed Financial Statements, Captions [Line Items]
Interest Rate	5.50%	5.50%
Recourse Debt Total	$ 573	$ 573
Parent Company | Recourse Debt | 6.00% senior notes due 2026 [Domain]
Condensed Financial Statements, Captions [Line Items]
Interest Rate	6.00%	6.00%
Recourse Debt Total	$ 500	$ 500
Parent Company | Recourse Debt | LIBOR | Senior Unsecured Note LIBOR plus 3% due 2019
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ 0	$ 240
Basis spread on variable rate	3.00%	3.00%
Parent Company | Recourse Debt | LIBOR | 8.00% Senior Unsecured Note Due 2020
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ 228	$ 469
Parent Company | Recourse Debt Excluding Junior Subordinated Debt
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	4,630	4,154
Recourse Debt Non Current	4,625	$ 4,154
Debt Maturity Year One [Member] | Parent Company
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	5
Debt Maturity Year Two [Member] | Parent Company
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	5
Debt Maturity Year Three [Member] | Parent Company
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	234
Debt Maturity Year Four [Member] | Parent Company
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	902
Debt Maturity Year Five [Member] | Parent Company
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	500
Debt Maturity Thereafter [Member] | Parent Company
Condensed Financial Statements, Captions [Line Items]
Recourse Debt Total	$ 3,024

Schedule I - Condensed Finan178

Schedule I - Condensed Financial Information of Parent (Dividends from Subsidiaries and Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries	$ 1,200	$ 1,026	$ 748

Schedule I - Condensed Finan179

Schedule I - Condensed Financial Information of Parent (Guarantees and Letters of Credit) (Details)	12 Months Ended
	Dec. 31, 2017USD ($)agreement
Condensed Financial Statements, Captions [Line Items]
Obligations number of agreements | agreement	47
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 930,000,000
Parent Company
Condensed Financial Statements, Captions [Line Items]
Letter of credit, fee range minimum	0.25%
Letter of credit, fee range maximum	2.25%
Guarantees | Parent Company
Condensed Financial Statements, Captions [Line Items]
Obligations, Minimum Individual Exposures	$ 1,000,000
Obligations, individual exposures (minimum less than $1 million)	$ 272,000,000
Guarantees and Asset Sale Related Indemnities (Combined) [Member]
Condensed Financial Statements, Captions [Line Items]
Obligations number of agreements | agreement	22
Guarantees and Asset Sale Related Indemnities (Combined) [Member] | Parent Company
Condensed Financial Statements, Captions [Line Items]
Obligations maximum exposure, total	$ 842,000,000
Letter of Credit | Parent Company
Condensed Financial Statements, Captions [Line Items]
Obligations, individual exposures (minimum less than $1 million)	13,000,000
Cash Collateralized Letters Of Credit | Parent Company
Condensed Financial Statements, Captions [Line Items]
Obligations, Minimum Individual Exposures	2,000,000
Cash Collateralized Letters Of Credit | Parent Company | Maximum
Condensed Financial Statements, Captions [Line Items]
Obligations, individual exposures (minimum less than $1 million)	$ 26,000,000
Unsecured Debt [Member] | Financial Standby Letter of Credit [Member]
Condensed Financial Statements, Captions [Line Items]
Obligations number of agreements | agreement	4
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 52,000,000
Secured Debt [Member] | Standby Letters of Credit [Member]
Condensed Financial Statements, Captions [Line Items]
Obligations number of agreements | agreement	21
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 36,000,000

Uncategorized Items - aes-20171

Label	Element	Value
Acquire addition shares through December 31, 2015 [Member]
Investment Options, acquisition percentage	aes_InvestmentOptionsacquisitionpercentage	2.00%
Dominican Republic [Member] | Acquire additional shares through December 31, 2017 [Member]
Investment Options, acquisition percentage	aes_InvestmentOptionsacquisitionpercentage	10.00%