General and Summary of Significant Accounting Policies Effect of Change in Estimate (Tables)

12 Months Ended

Dec. 31, 2018

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 an impact on the Company’s consolidated financial statements. Accounting pronouncements not listed below were assessed and determined to be either not applicable or did not have a 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
2018-15, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract	This standard aligns the accounting for implementation costs incurred for a cloud computing arrangement that is a service with the requirement for capitalizing implementation costs associated with developing or obtaining internal-use software. Transition method: retrospective or prospective.	October 1, 2018	The Company elected to early-adopt this standard on a prospective basis, effective for fiscal year 2018. The adoption of this standard did not have a material impact on the financial statements.
2018-14, Compensation— Retirement Benefits — Defined Benefit Plans — General (Subtopic 715-20): Disclosure Framework	This standard modifies the disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans. Transition method: retrospective.	Early adoption elected, January 1, 2018	Impact limited to changes in financial statement disclosures.
2017-07, Compensation — Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost	This standard changes the presentation of non-service costs associated with defined benefit and other postretirement plans and updates the guidance so that only the service cost component will be eligible for capitalization. Transition method: retrospective for presentation of non-service cost and prospective for the change in capitalization.	January 1, 2018	For the year ended December 31, 2017 and 2016, $1 million and $3 million of non-service costs associated with defined benefit and other postretirement plans were reclassified from Costs of Sales to Other Expense, respectively.
2017-05, Other Income — Gains and Losses from the Derecognition of Nonfinancial Assets (Topic 610-20): Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets	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 provides guidance on how gains and losses on transfers of nonfinancial assets and in substance nonfinancial assets to non-customers are recognized. The standard also clarifies that the derecognition of businesses is under the 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. Transition method: modified retrospective.	January 1, 2018	Following adoption of ASU 2017-01, fewer transactions are expected to meet the definition of a business under the scope of ASC 810 and will fall under the scope under this standard.

2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment	This standard simplifies the accounting for goodwill impairments by removing the requirement to calculate the implied fair value of goodwill by assigning the fair value of a reporting unit to all of its assets and liabilities as if it had been acquired in a business combination. Instead, it requires that an entity record an impairment charge based on the amount by which a reporting unit's carrying amount exceeds its fair value, not to exceed the total amount of goodwill allocated to that reporting unit. Transition method: prospective.	October 1, 2018	In anticipation of our annual goodwill process, the Company early-adopted this standard to ease the administrative burden for the measurement of any potential goodwill impairment losses. There was no impact to the financial statements upon adoption of the standard.
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, at least one substantive process should exist to be considered a business. Transition method: prospective.	January 1, 2018	Some acquisitions and dispositions are expected to now fall under a different accounting model. This will reduce the number of transactions that are accounted for as business combinations and therefore future acquired goodwill.
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. Transition method: retrospective.	January 1, 2018	For the years ended December 31, 2017 and 2016, cash provided by operating activities increased by $15 million and $13 million, respectively, cash used in investing activities decreased by $150 million and increased by $28 million, respectively, and cash provided by financing activities was unchanged.
2016-01, Financial Instruments — Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities	The standard significantly revises an entity’s accounting related to (1) classification and measurement of investments in equity securities and (2) the presentation of certain fair value changes for financial liabilities measured at fair value. It also amends certain disclosures of financial instruments. Transition method: modified retrospective. Prospective for equity investments without readily determinable fair value.	January 1, 2018	No material impact upon adoption of the standard.
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	See impact upon adoption of the standard below.

On January 1, 2018, the Company adopted ASU 2014-09, "Revenue from Contracts with Customers," and its subsequent corresponding updates ("ASC 606"). Under this standard, an entity shall recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The Company applied the modified retrospective method of adoption to the contracts that were not completed as of January 1, 2018. Results for reporting periods beginning January 1, 2018 are presented under ASC 606, while prior period amounts were not adjusted and continue to be reported in accordance with the previous revenue recognition standard. For contracts that were modified before January 1, 2018, the Company reflected the aggregate effect of all modifications when identifying the satisfied and unsatisfied performance obligations, determining the transaction price and allocating the transaction price.

The cumulative effect to our January 1, 2018 Consolidated Balance Sheet resulting from the adoption of ASC 606 was as follows (in millions):

Consolidated Balance Sheet	Balance at December 31, 2017			Adjustments Due to ASC 606			Balance at January 1, 2018
Assets
Other current assets	$	630		$	61		$	691
Deferred income taxes	130			(24		)	106
Service concession assets, net	1,360			(1,360		)	—
Loan receivable	—			1,490			1,490
Equity
Accumulated deficit	(2,276		)	67			(2,209		)
Accumulated other comprehensive loss	(1,876		)	19			(1,857		)
Noncontrolling interest	2,380			81			2,461

The Mong Duong II power plant in Vietnam is the primary driver of changes in revenue recognition under the new standard. This plant is operated under a build, operate, and transfer contract and will be transferred to the Vietnamese government after the completion of a 25-year PPA. Under the previous revenue recognition standard, construction costs were deferred to a service concession asset, which was expensed in proportion to revenue recognized for the construction element over the term of the PPA. Under ASC 606, construction revenue and associated costs are recognized as construction activity occurs. As construction of the plant was substantially completed in 2015, revenues and costs associated with the construction were recognized through retained earnings, and the service concession asset was derecognized. A loan receivable was recognized for the future expected payments for the construction performance obligation. As the payments for the construction performance obligation occur over a 25-year term, a significant financing element was determined to exist which is accounted for under the effective interest rate method. The other performance obligation to operate and maintain the facility is measured based on the capacity made available.

The impact to our Consolidated Balance Sheet as of December 31, 2018 resulting from the adoption of ASC 606 as compared to the previous revenue recognition standard was as follows (in millions):

	December 31, 2018
Consolidated Balance Sheet	As Reported			Balances Without Adoption of ASC 606			Adoption Impact
Assets
Other current assets	$	807		$	741		$	66
Deferred income taxes	97			122			(25		)
Service concession assets, net	—			1,261			(1,261		)
Loan receivable	1,423			—			1,423
TOTAL ASSETS	32,521			32,318			203
Equity
Accumulated deficit	(1,005		)	(1,112		)	107
Accumulated other comprehensive loss	(2,071		)	(2,088		)	17
Noncontrolling interest	2,396			2,317			79
TOTAL LIABILITIES AND EQUITY	32,521			32,318			203

The impact to our Consolidated Statement of Operations for the year ended December 31, 2018 resulting from the adoption of ASC 606 as compared to the previous revenue recognition standard was as follows (in millions):

	Year Ended December 31, 2018
Consolidated Statement of Operations	As Reported			Balances Without Adoption of ASC 606			Adoption Impact
Total revenue	$	10,736		$	10,800		$	(64	)
Total cost of sales	(8,163		)	(8,207		)	44
Operating margin	2,573			2,593			(20		)
Interest income	310			252			58
Other Income	72			70			2
Income from continuing operations before taxes and equity in earnings of affiliates	2,018			1,978			40
INCOME FROM CONTINUING OPERATIONS	1,349			1,309			40
NET INCOME	1,565			1,525			40
NET INCOME ATTRIBUTABLE TO THE AES CORPORATION	1,203			1,163			40

New Accounting Pronouncements Issued But Not Yet Effective — The following table provides a brief description of recent accounting pronouncements that could have a material impact on the Company’s consolidated financial statements once adopted. 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 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 does not expect any impact on its consolidated financial statements upon adoption of the standard on January 1, 2019.
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 in the period in which it settles. 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.
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, 2018-10, 2018-11, 2018-20 Leases (Topic 842)	See discussion of the ASU below.	January 1, 2019. Early adoption is permitted.	The Company will adopt the standard on January 1, 2019; 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]

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