Ipalco Enterprises 10-Q 8 May 17 2017 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2017	May 05, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2017
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2,017
Entity Registrant Name	IPALCO ENTERPRISES, INC.
Entity Central Index Key	728,391
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		108,907,318

Unaudited Condensed Consolidate

Unaudited Condensed Consolidated Statements Of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
UTILITY OPERATING REVENUES	$ 336,909	$ 327,745
Operation:
Fuel	70,735	66,497
Other operating expenses	64,127	57,234
Power purchased	49,021	52,448
Maintenance	30,027	30,521
Depreciation and amortization	52,544	53,235
Taxes other than income taxes	12,274	11,134
Income taxes - net	15,953	16,404
Total utility operating expenses	294,681	287,473
UTILITY OPERATING INCOME	42,228	40,272
OTHER INCOME AND (DEDUCTIONS):
Allowance for equity funds used during construction	6,425	6,781
Miscellaneous income and (deductions) - net	(344)	(1,076)
Income tax benefit applicable to nonoperating income	3,770	3,463
Total other income and (deductions) - net	9,851	9,168
INTEREST AND OTHER CHARGES:
Interest on long-term debt	29,121	26,101
Other interest	367	742
Allowance for borrowed funds used during construction	(5,482)	(5,834)
Amortization of redemption premiums and expense on debt	1,077	1,026
Total interest and other charges - net	25,083	22,035
NET INCOME	26,996	27,405
LESS: PREFERRED DIVIDENDS OF SUBSIDIARY	803	803
NET INCOME APPLICABLE TO COMMON STOCK	$ 26,193	$ 26,602

Unaudited Condensed Consolidat3

Unaudited Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
UTILITY PLANT:
Utility plant in service	$ 5,015,126	$ 4,997,846
Less accumulated depreciation	2,048,423	2,030,497
Utility plant in service - net	2,966,703	2,967,349
Construction work in progress	922,662	898,330
Spare parts inventory	13,272	14,237
Property held for future use	1,002	1,002
Utility plant - net	3,903,639	3,880,918
OTHER ASSETS:
Nonutility property - at cost, less accumulated depreciation	510	512
Intangible Assets, Net (Excluding Goodwill)	11,208	11,976
Other long-term assets	5,670	5,916
Other assets - net	17,388	18,404
CURRENT ASSETS:
Cash and cash equivalents	34,410	34,953
Accounts receivable and unbilled revenue (less allowance for doubtful accounts of $3,262 and $2,498, respectively)	139,146	154,586
Fuel inventories - at average cost	35,750	30,237
Materials and supplies - at average cost	59,917	60,648
Regulatory assets	32,040	33,912
Prepayments and other current assets	35,252	33,504
Total current assets	336,515	347,840
DEFERRED DEBITS:
Regulatory assets	444,209	450,710
Miscellaneous	5,522	4,409
Total deferred debits	449,731	455,119
TOTAL	4,707,273	4,702,281
Common shareholders' equity:
Paid in capital	596,966	596,810
Accumulated deficit	(24,533)	(25,627)
Total common shareholders' equity	572,433	571,183
Cumulative preferred stock of subsidiary	59,784	59,784
Long-term debt (Note 5)	2,475,596	2,474,840
Total capitalization	3,107,813	3,105,807
CURRENT LIABILITIES:
Short-term and current portion of long-term debt (Note 5)	84,650	74,650
Accounts payable	93,483	119,511
Accrued expenses	20,511	18,754
Accrued real estate and personal property taxes	23,544	18,930
Regulatory liabilities	4,829	7,704
Accrued Income Taxes, Current	16,603	0
Accrued interest	42,201	32,541
Customer deposits	30,228	29,780
Other current liabilities	14,980	19,467
Total current liabilities	331,029	321,337
DEFERRED CREDITS AND OTHER LONG-TERM LIABILITIES:
Regulatory liabilities	676,676	670,294
Deferred income taxes - net	446,743	449,730
Non-current income tax liability	6,625	6,634
Unamortized investment tax credit	2,065	2,410
Accrued pension and other postretirement benefits	54,003	64,139
Asset retirement obligations	80,754	80,568
Miscellaneous	1,565	1,362
Total deferred credits and other long-term liabilities	1,268,431	1,275,137
COMMITMENTS AND CONTINGENCIES
TOTAL	$ 4,707,273	$ 4,702,281

Unaudited Condensed Consolidat4

Unaudited Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Accounts receivable and unbilled revenue, allowance for doubtful accounts	$ 3,262	$ 2,498

Unaudited Condensed Consolidat5

Unaudited Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
CASH FLOWS FROM OPERATIONS:
Net income	$ 26,996	$ 27,405
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	52,591	52,837
Amortization of regulatory assets	261	1,395
Amortization of debt premium	710	30
Deferred income taxes and investment tax credit adjustments - net	(6,509)	12,942
Allowance for equity funds used during construction	(6,425)	(6,684)
Change in certain assets and liabilities:
Accounts receivable	15,440	(2,813)
Fuel, materials and supplies	(4,721)	6,874
Increase (Decrease) in Income Taxes Payable	(18,692)	0
Income taxes receivable or payable	3,134	2,726
Accounts payable and accrued expenses	(12,343)	688
Accrued real estate and personal property taxes	4,614	3,653
Accrued interest	9,660	6,343
Pension and other postretirement benefit expenses	(10,135)	(18,464)
Short-term and long-term regulatory assets and liabilities	6,588	(10,544)
Prepaids and other current assets	(6,971)	(9,433)
Other - net	(3,306)	1,835
Net cash provided by operating activities	88,276	68,790
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures - utility	(64,298)	(234,516)
Project development costs	(333)	(195)
Cost of removal, net of salvage	(2,656)	(5,556)
Other	(395)	(696)
Net cash used in investing activities	(67,682)	(240,963)
CASH FLOWS FROM FINANCING ACTIVITIES:
Short-term debt borrowings	25,000	148,000
Short-term debt repayments	(15,000)	(83,000)
Dividends on common stock	(25,099)	(24,500)
Issuance of common stock	0	134,276
Preferred dividends of subsidiary	(803)	(803)
Deferred financing costs paid	(107)	(45)
Payments for financed capital expenditures	(4,900)	(3,198)
Other	(228)	(154)
Net cash (used in) provided by financing activities	(21,137)	170,576
Net change in cash and cash equivalents	(543)	(1,597)
Cash and cash equivalents at beginning of period	34,953	21,521
Cash and cash equivalents at end of period	34,410	19,924
Cash paid during the period for:
Interest (net of amount capitalized)	14,310	14,655
Income taxes	0	0
Non-cash investing activities:
Accruals for capital expenditures	$ 21,983	$ 81,371

Overview and Summary Of Signifi

Overview and Summary Of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Overview and Summary Of Significant Accounting Policies	OVERVIEW AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES IPALCO is a holding company incorporated under the laws of the state of Indiana. IPALCO, acquired by AES in March 2001, is owned by AES U.S. Investments ( 82.35% ) and CDPQ ( 17.65% ). AES U.S. Investments is owned by AES U.S. Holdings, LLC ( 85% ) and CDPQ ( 15% ). IPALCO owns all of the outstanding common stock of IPL. Substantially all of IPALCO’s business consists of generating, transmitting, distributing and selling of electric energy conducted through its principal subsidiary, IPL. IPL was incorporated under the laws of the state of Indiana in 1926. IPL has approximately 490,000 retail customers in the city of Indianapolis and neighboring cities, towns and communities, and adjacent rural areas all within the state of Indiana, with the most distant point being approximately forty miles from Indianapolis. IPL has an exclusive right to provide electric service to those customers. IPL owns and operates four generating stations, all within the state of Indiana. IPL’s largest generating station, Petersburg, is coal-fired. The second largest station, Harding Street, has converted its coal-fired units to natural gas and uses natural gas and fuel oil to power combustion turbines. In addition, IPL began the operation of a 20 MW battery energy storage unit, which provides frequency response, at this location in May 2016. The third station, Eagle Valley, retired its coal-fired units in April 2016. The CCGT at Eagle Valley is expected to be completed in the first half of 2018 with a rated output of 671 MW. The fourth station, Georgetown, is a small peaking station that uses natural gas to power combustion turbines. As of March 31, 2017, IPL’s net electric generation capacity for winter is 2,996 MW and net summer capacity is 2,881 MW. Principles of Consolidation The accompanying Financial Statements include the accounts of IPALCO, IPL and Mid-America Capital Resources, Inc., a non-regulated wholly-owned subsidiary of IPALCO. All significant intercompany amounts have been eliminated. The accompanying Financial Statements are unaudited; however, they have been prepared in accordance with GAAP for interim financial information and in conjunction with the rules and regulations of the SEC. Accordingly, they do not include all of the disclosures required by GAAP for annual fiscal reporting periods. In the opinion of management, all adjustments of a normal recurring nature necessary for fair presentation have been included. The electric utility business is affected by seasonal weather patterns throughout the year and, therefore, the operating revenues and associated operating expenses are not generated evenly by month during the year. These unaudited Financial Statements have been prepared in accordance with the accounting policies described in IPALCO’s 2016 Form 10-K and should be read in conjunction therewith. Use of Management Estimates The preparation of financial statements in conformity with GAAP requires that management make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements. The reported amounts of revenues and expenses during the reporting period may also be affected by the estimates and assumptions that management is required to make. Actual results may differ from those estimates. 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 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 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. Transition method: The recognition of excess tax benefits and tax deficiencies arising from vesting or settlement were applied retrospectively. The elimination of the requirement that excess tax benefits be realized before they are recognized was adopted on a modified retrospective basis with a cumulative adjustment to the opening balance sheet. January 1, 2017 The primary effect of adoption was the recognition of excess tax benefits in our 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. We will continue to estimate the number of awards that are expected to vest in our determination of the related periodic compensation cost. The adoption of this standard did not have a material impact on the 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 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 of the premium on certain callable debt securities to the earliest call date. Transition method: modified retrospective. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2017-07, Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost The standard provides guidance on the presentation of net benefit cost in an employer’s income statement and on the components eligible for capitalization. It requires that an employer report the service cost component in the same line item(s) as other employee compensation costs arising from services rendered during the period, and report the other components of net benefit cost separately from the service cost component and outside a subtotal of operating income. Only the service cost component will be eligible for capitalization. Transition method: various. January 1, 2018. Early adoption is permitted. 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 This standard provides guidance to assist entities with evaluating when a set of transferred assets and activities is a business. Transition method: prospective. January 1, 2018. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2016-18, Statement of Cash Flows (Topic 320): 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 Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory This standard requires that an entity recognizes the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Transition method: modified retrospective. January 1, 2018 Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Receipts and Cash Payments (a consensus of the Emerging Issues Task Force) This standard provides specific guidance on how certain cash transactions are presented and classified in the statement of cash flows. Transition method: retrospective. January 1, 2018. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard, but does not anticipate a material impact 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 to an expected loss model rather than an incurred loss model. It also allows for the presentation of credit losses on available-for-sale debt securities as an allowance rather than a write down. 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, Leases (Topic 842) The standard creates Topic 842, Leases, which supersedes Topic 840, Leases. It introduces a lessee model that brings substantially all leases onto the balance sheet while retaining most of the principles of the existing lessor model in U.S. GAAP and aligning many of those principles with ASC 606, Revenue from Contracts with Customers. Transition method: modified retrospective approach with certain practical expedients. January 1, 2019. Early adoption is permitted. The Company is currently evaluating the impact of adopting the standard on its consolidated financial statements. The Company intends to adopt the standard as of January 1, 2019. 2014-09, 2015-14, 2016-08, 2016-10, 2016-12, 2016-20, 2017-05, Revenue from Contracts with Customers (Topic 606) See discussion of this ASU below: January 1, 2018. Earlier application 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. ASU 2014-09 and its subsequent corresponding updates provide the principles an entity must apply to measure and recognize revenue. The core principle is that 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. Amendments to the standard were issued to provide further clarification of the principle and certain transition expedients. The standard will replace most existing revenue recognition guidance in GAAP, including the guidance on recognizing other income upon the sale or transfer of non-financial assets (including in-substance real estate). The standard requires retrospective application and allows either a full retrospective adoption in which all of the periods are presented under the new standard or a modified retrospective approach in which the cumulative effect of initially applying the guidance is recognized at the date of initial application. We are currently working towards adopting the standard using the full retrospective method. However, the Company will continue to assess this conclusion which is dependent on the final impact to the Financial Statements. In 2016, the Company established a cross-functional implementation team and is in the process of evaluating changes to our business processes, systems and controls to support recognition and disclosure under the new standard. At this time, we do not expect any significant impact on our business and financial systems as a result of the implementation of the new revenue recognition standard. The Company is currently evaluating certain contracts along with our tariff revenue and certain revenue arrangements with MISO (i.e., capacity and wholesale agreements). The Company expects additional contracts to be executed during 2017 that will require assessment under the new standard. Through this assessment, the Company has identified certain key issues that we are continuing to evaluate in order to complete our assessment of the full population of contracts and assess the overall impact to the Financial Statements. These issues include: the application of the practical expedient for measuring progress toward satisfaction of a performance obligation, when variable quantities would be considered variable consideration versus an option to acquire additional goods and services, and how to measure progress toward completion for a performance obligation that is a bundle. We are continuing to work with various non-authoritative industry groups and monitoring the FASB and Transition Resource Group (TRG) activity, as we finalize our accounting policy on these and other industry specific interpretative issues which are expected in 2017.

Regulatory Matters

Regulatory Matters	3 Months Ended
	Mar. 31, 2017
Regulated Operations [Abstract]
Regulatory Matters	REGULATORY MATTERS In March 2016, the IURC issued the 2016 Rate Order authorizing IPL to increase its basic rates and charges by $30.8 million annually. The order also authorized IPL to collect, over a ten year period, $117.7 million of previously deferred regulatory assets related to IPL’s participation in the regional transmission organization known as MISO. Such deferred costs will be amortized to expense over ten years. Accordingly, $11.8 million of IPL’s long-term MISO regulatory asset is included within current regulatory assets on the accompanying Unaudited Condensed Consolidated Balance Sheets. The rate order also authorized an increase in IPL’s depreciation rates of $24.3 million annually compared to the twelve months ended June 30, 2014, which is the period upon which the rate increase was calculated. IPL also received approval to implement three new rate riders for current recovery from customers of ongoing MISO costs and capacity costs, and for sharing with customers 50% of wholesale sales margins above and below the established annual benchmark of $6.3 million . Additionally, the capacity rider provides that IPL will share with customers 50% of any capacity sales. The order approved recovery of IPL’s pension expenses and a return on IPL’s discretionary pension fundings. While the IURC noted in the order that they found IPL’s Service Company cost allocations to be reasonable, IPL was directed to request the FERC to review its Service Company allocations. Such review is currently underway. The IURC also closed their investigation into IPL’s underground network. Some of the intervening parties in the IURC rate case filed petitions for reconsideration of the IURC’s March 2016 order with respect to certain issues. These petitions were subsequently denied by the IURC. In addition, certain intervening parties have filed notices of appeal of the order. On April 5, 2017, the Indiana Court of Appeals affirmed the IURC’s March 2016 order. In May 2014, IPL received an order from the IURC granting approval to build a 644 to 685 MW CCGT at Eagle Valley. The costs to build and operate the CCGT, other than fuel costs, will not be recoverable by IPL through rates until the conclusion of a base rate case proceeding with the IURC after construction is completed. On December 22, 2016, IPL filed a petition with the IURC for authority to increase its basic rates and charges primarily to recover the cost of the new CCGT. The CCGT was previously expected to be completed in the first half of 2017, but is now expected to be completed in the first half of 2018. To address this change, on February 24, 2017, IPL filed a motion to withdraw the case without prejudice or alternatively amend the petition and case-in-chief at a later date. On March 15, 2017, the IURC dismissed the rate case without prejudice. IPL will file a new base rate case with the IURC to coincide with the completion of the CCGT.

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE Fair Value Hierarchy ASC 820 defined and established a framework for measuring fair value and expands disclosures about fair value measurements for financial assets and liabilities that are adjusted to fair value on a recurring basis and/or financial assets and liabilities that are measured at fair value on a nonrecurring basis, which have been adjusted to fair value during the period. In accordance with ASC 820, we have categorized our financial assets and liabilities that are adjusted to fair value, based on the priority of the inputs to the valuation technique, following the three-level fair value hierarchy prescribed by ASC 820 as follows: Level 1 - unadjusted quoted prices for identical assets or liabilities in an active market; Level 2 - inputs from quoted prices in markets where trading occurs infrequently or quoted prices of instruments with similar attributes in active markets; and Level 3 - unobservable inputs reflecting management’s own assumptions about the inputs used in pricing the asset or liability. As of March 31, 2017 and December 31, 2016 , all of IPALCO’s financial assets or liabilities adjusted to fair value on a recurring basis (excluding pension assets – see Note 7, “ Benefit Plans ”) were considered Level 3, based on the above fair value hierarchy. These primarily consisted of FTRs, which are used to offset MISO congestion charges. Because the benefit associated with FTRs is a flow-through to IPL’s jurisdictional customers, IPL records a regulatory liability matching the value of the FTRs. In addition, IPALCO had one financial asset, a nonutility investment accounted for using the cost method of accounting, which is measured at fair value on a nonrecurring basis, again using Level 3 measurements. All of these financial assets and liabilities were not material to the Financial Statements in the periods covered by this report, individually or in the aggregate. Whenever possible, quoted prices in active markets are used to determine the fair value of our financial instruments. Our financial instruments are not held for trading or other speculative purposes. The estimated fair value of financial instruments has been determined by using available market information and appropriate valuation methodologies. However, considerable judgment is required in interpreting market data to develop the estimates of fair value. Accordingly, the estimates presented herein are not necessarily indicative of the amounts that we could realize in a current market exchange. The use of different market assumptions and/or estimation methodologies may have a material effect on the estimated fair value amounts. Non-Recurring Fair Value Measurements ASC 410 “Asset Retirement and Environmental Obligations” addresses financial accounting and reporting for legal obligations associated with the retirement of long-lived assets that result from acquisition, construction, development and/or normal operation. A legal obligation for purposes of ASC 410 is an obligation that a party is required to settle as a result of an existing law, statute, ordinance, written or oral contract or the doctrine of promissory estoppel. IPL’s ARO liabilities relate primarily to environmental issues involving asbestos-containing materials, ash ponds, landfills and miscellaneous contaminants associated with its generating plants, transmission system and distribution system. We use the cost approach to determine the fair value of IPL’s ARO liabilities, which is estimated by discounting expected cash outflows to their present value at the initial recording of the liabilities. Cash outflows are based on the approximate future disposal costs as determined by market information, historical information or other management estimates. These inputs to the fair value of the ARO liabilities would be considered Level 3 inputs under the fair value hierarchy. As of March 31, 2017 and December 31, 2016 , ARO liabilities were $80.8 million and $80.6 million , respectively. Financial Instruments not Measured at Fair Value in the Consolidated Balance Sheets Debt The fair value of our outstanding fixed-rate debt has been determined on the basis of the quoted market prices of the specific securities issued and outstanding. In certain circumstances, the market for such securities was inactive and therefore the valuation was adjusted to consider changes in market spreads for similar securities. Accordingly, the purpose of this disclosure is not to approximate the value on the basis of how the debt might be refinanced. The following table shows the face value and the fair value of fixed-rate and variable-rate indebtedness (Level 2) for the periods ending: March 31, 2017 December 31, 2016 Face Value Fair Value Face Value Fair Value (In Millions) Fixed-rate $ 2,438.5 $ 2,564.3 $ 2,438.5 $ 2,543.5 Variable-rate 150.0 150.0 140.0 140.0 Total indebtedness $ 2,588.5 $ 2,714.3 $ 2,578.5 $ 2,683.5 The difference between the face value and the carrying value of this indebtedness represents the following: • unamortized deferred financing costs of $21.5 million and $22.2 million at March 31, 2017 and December 31, 2016, respectively; and • unamortized discounts of $6.7 million and $6.8 million at March 31, 2017 and December 31, 2016 , respectively.

Equity

Equity	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Equity	EQUITY On March 1, 2016, IPALCO issued and sold 7,403,213 shares of IPALCO’s common stock to CDPQ for $134.3 million under the Subscription Agreement. After completion of these transactions, CDPQ’s direct and indirect interests in IPALCO total approximately 30% . On June 1, 2016, IPALCO received equity capital contributions of $64.8 million from AES U.S. Investments and $13.9 million from CDPQ. IPALCO then made the same investments in IPL. The proceeds were primarily used for funding needs related to IPL’s environmental and replacement generation projects. The capital contributions on June 1, 2016 were made on a proportional share basis and, therefore, did not change CDPQ’s or AES’ ownership interests in IPALCO.

Debt

Debt	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Indebtedness	DEBT Long-Term Debt The following table presents our long-term debt: March 31, December 31, Series Due 2017 2016 (In Thousands) IPL first mortgage bonds: 5.40% (1) August 2017 $ 24,650 $ 24,650 3.875% (2) August 2021 55,000 55,000 3.875% (2) August 2021 40,000 40,000 3.125% (2) December 2024 40,000 40,000 6.60% January 2034 100,000 100,000 6.05% October 2036 158,800 158,800 6.60% June 2037 165,000 165,000 4.875% November 2041 140,000 140,000 4.65% June 2043 170,000 170,000 4.50% June 2044 130,000 130,000 4.70% September 2045 260,000 260,000 4.05% May 2046 350,000 350,000 Unamortized discount – net (6,446 ) (6,477 ) Deferred financing costs (16,557 ) (16,736 ) Total IPL first mortgage bonds 1,610,447 1,610,237 IPL unsecured debt: Variable (3) December 2020 30,000 30,000 Variable (3) December 2020 60,000 60,000 Deferred financing costs (428 ) (456 ) Total IPL unsecured debt 89,572 89,544 Total Long-term Debt – IPL 1,700,019 1,699,781 Long-term Debt – IPALCO: 5.00% Senior Secured Notes May 2018 400,000 400,000 3.45% Senior Secured Notes July 2020 405,000 405,000 Unamortized discount – net (247 ) (273 ) Deferred financing costs (4,526 ) (5,018 ) Total Long-term Debt – IPALCO 800,227 799,709 Total Consolidated IPALCO Long-term Debt 2,500,246 2,499,490 Less: Current Portion of Long-term Debt 24,650 24,650 Net Consolidated IPALCO Long-term Debt $ 2,475,596 $ 2,474,840 (1) First mortgage bonds are issued to the city of Petersburg, Indiana, to secure the loan proceeds from various tax-exempt bonds issued by the city. (2) First mortgage bonds are issued to the Indiana Finance Authority, to secure the loan of proceeds from tax-exempt bonds issued by the Indiana Finance Authority. (3) Unsecured notes are issued to the Indiana Finance Authority by IPL to facilitate the loan of proceeds from various tax-exempt notes issued by the Indiana Finance Authority. The notes have a final maturity date of December 2038, but are subject to a mandatory put in December 2020. IPALCO’s Senior Secured Notes IPALCO has $400 million of 5.00% Senior Secured Notes due May 1, 2018. Although current liquid funds are not sufficient to pay these notes at maturity, we believe that we will be able to refinance these notes based on our conversations with investment bankers, which currently indicate more than adequate demand for new IPALCO debt at our current credit rating; and the previous successful issuance of our $400 million IPALCO senior secured notes in 2015, which served to refinance existing notes. Should the capital markets not be accessible to IPALCO at the time of the maturity of the 2018 IPALCO Notes, management believes that other financing options are at its disposal to meet the needs of the maturity. Line of Credit IPL entered into an amendment and restatement of its 5 -year $250 million revolving credit facility in May 2014, and a further amendment and extension of the credit facility on October 16, 2015 with a syndication of banks. This Credit Agreement is an unsecured committed line of credit to be used: (i) to finance capital expenditures; (ii) to refinance indebtedness under the existing credit agreement; (iii) to support working capital; and (iv) for general corporate purposes. This agreement matures on October 16, 2020 , and bears interest at variable rates as described in the Credit Agreement. It includes an uncommitted $150 million accordion feature to provide IPL with an option to request an increase in the size of the facility at any time prior to October 16, 2019, subject to approval by the lenders. Prior to execution, IPL and IPALCO had existing general banking relationships with the parties to the Credit Agreement. As of March 31, 2017 and December 31, 2016 , IPL had $60.0 million and $50.0 million in outstanding borrowings on the committed line of credit, respectively.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES IPALCO’s effective combined state and federal income tax rate was 31.8% for the three months ended March 31, 2017, as compared to 32.7% for the three months ended March 31, 2016. The decrease in the effective tax rate versus the comparable period was primarily due to the manufacturer’s production deduction (Internal Revenue Code Section 199) that had been previously limited due to a Net Operating Loss carryover.

Benefit Plans

Benefit Plans	3 Months Ended
	Mar. 31, 2017
Compensation and Retirement Disclosure [Abstract]
Benefit Plans	BENEFIT PLANS The following table (in thousands) presents information for the three months ended March 31, 2017 , relating to the Pension Plans: Net unfunded status of plans: Net unfunded status at December 31, 2016, before tax adjustments $ (57,395 ) Net benefit cost components reflected in net unfunded status during first quarter: Service cost (1,836 ) Interest cost (6,327 ) Expected return on assets 11,167 Actuarial valuation adjustment 80 Employer contributions 7,211 Net unfunded status at March 31, 2017, before tax adjustments $ (47,100 ) Regulatory assets related to pensions (1) : Regulatory assets at December 31, 2016, before tax adjustments $ 223,705 Amount reclassified through net benefit cost: Amortization of prior service cost (1,060 ) Amortization of net actuarial loss (3,300 ) Settlements (2) (146 ) Actuarial valuation adjustment (80 ) Regulatory assets at March 31, 2017, before tax adjustments $ 219,119 (1) Amounts that would otherwise be charged/credited to Accumulated Other Comprehensive Income or Loss upon application of ASC 715, “Compensation – Retirement Benefits,” are recorded as a regulatory asset or liability because IPL has historically recovered and currently recovers pension and other postretirement benefit expenses in rates. These are unrecognized amounts not yet recognized as components of net periodic benefit costs. (2) The settlement loss of $0.1 million for the three months ended March 31, 2017 was the result of a lump sum distribution paid out of the Supplemental Retirement Plan. Pension Expense The following table presents net periodic benefit cost information relating to the Pension Plans combined: For the Three Months Ended, March 31, 2017 2016 (In Thousands) Components of net periodic benefit cost: Service cost $ 1,836 $ 1,754 Interest cost 6,327 6,454 Expected return on plan assets (11,167 ) (10,873 ) Amortization of prior service cost 1,060 1,296 Amortization of actuarial loss 3,300 3,474 Settlements 146 — Net periodic benefit cost $ 1,502 $ 2,105 In addition, IPL provides postretirement health care benefits to certain active or retired employees and the spouses of certain active or retired employees. These postretirement health care benefits and the related unfunded obligation of $7.0 million and $6.8 million at March 31, 2017 and December 31, 2016 , respectively, were not material to the Financial Statements in the periods covered by this report.

Commitments And Contingencies

Commitments And Contingencies	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	COMMITMENTS AND CONTINGENCIES Legal Loss Contingencies IPALCO and IPL are involved in litigation arising in the normal course of business. While the results of such litigation cannot be predicted with certainty, management believes that the final outcome will not have a material adverse effect on IPALCO’s results of operations, financial condition and cash flows. Amounts accrued or expensed for legal or environmental contingencies collectively during the periods covered by this report have not been material to the Financial Statements. Environmental Loss Contingencies We are subject to various federal, state, regional and local environmental protection and health and safety laws and regulations governing, among other things, the generation, storage, handling, use, disposal and transportation of hazardous materials; the emission and discharge of hazardous and other materials into the environment; and the health and safety of our employees. These laws and regulations often require a lengthy and complex process of obtaining and renewing permits and other governmental authorizations from federal, state and local agencies. Violation of these laws, regulations or permits can result in substantial fines, other sanctions, permit revocation and/or facility shutdowns. We cannot be certain that we have been or will be at all times in full compliance with such laws, regulations and permits. New Source Review and Other CAA NOVs In October 2009, IPL received a NOV and Finding of Violation from the EPA pursuant to the CAA Section 113(a). The NOV alleges violations of the CAA at IPL’s three primarily coal-fired electric generating facilities at the time, dating back to 1986. The alleged violations primarily pertain to the PSD and nonattainment New Source Review requirements under the CAA. In addition, on October 1, 2015, IPL received a NOV from the EPA pursuant to CAA Section 113(a) alleging violations of the CAA, the Indiana SIP, and the Title V operating permit related to alleged particulate matter and opacity violations at IPL Petersburg Unit 3. Also, on February 5, 2016, the EPA issued a NOV pursuant to CAA Section 113(a) alleging violations of New Source Review and other CAA regulations, the Indiana SIP, and the Title V operating permit at Petersburg Generating Station. Since receiving the letters, IPL management has met with the EPA staff regarding possible resolutions of the NOVs. Settlements and litigated outcomes of similar New Source Review cases have required companies to pay civil penalties, install additional pollution control technology on coal-fired electric generating units, retire existing generating units, and invest in additional environmental projects. A similar outcome in these cases could have a material impact on our business. It is too early to determine whether these NOVs could have a material impact on our business, financial condition or results of operations. We would seek recovery of any operating or capital expenditures, but not fines or penalties, related to air pollution control technology to reduce regulated air emissions; however, there can be no assurances that we would be successful in this regard. IPL has recorded a contingent liability related to these New Source Review cases and other CAA NOV matters.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2017
Segment Reporting [Abstract]
Segment Information	SEGMENT INFORMATION Operating segments are components of an enterprise that engage in business activities from which it may earn revenues and incur expenses, for which separate financial information is available, and is evaluated regularly by the chief operating decision maker in assessing performance and deciding how to allocate resources. Substantially all of our business consists of the generation, transmission, distribution and sale of electric energy conducted through IPL which is a vertically integrated electric utility. IPALCO’s reportable business segment is its utility segment, with all other non-utility business activities aggregated separately. The non-utility category primarily includes the 2018 IPALCO Notes and the 2020 IPALCO Notes; approximately $12.4 million and $8.3 million of cash and cash equivalents, as of March 31, 2017 and December 31, 2016 , respectively; long-term investments of $4.8 million and $5.2 million at March 31, 2017 and December 31, 2016 , respectively; and income taxes and interest related to those items. All other assets represented less than 1% of IPALCO’s total assets as of March 31, 2017 and December 31, 2016 . Net income for the utility segment was $32.3 million and $33.6 million for the three-month periods ended March 31, 2017 and 2016 , respectively. The accounting policies of the identified segment are consistent with those policies and procedures described in the summary of significant accounting policies. Intersegment sales, if any, are generally based on prices that reflect the current market conditions.

Overview and Summary Of Signi15

Overview and Summary Of Significant Accounting Policies (Policy)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Use Of Management Estimates	Use of Management Estimates The preparation of financial statements in conformity with GAAP requires that management make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements. The reported amounts of revenues and expenses during the reporting period may also be affected by the estimates and assumptions that management is required to make. Actual results may differ from those estimates.
Reclassifications	.
New Accounting Pronouncements	.

Overview and Summary Of Signi16

Overview and Summary Of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Schedule of New Accounting Pronouncements	.

Regulatory Matters (Tables)

Regulatory Matters (Tables)	3 Months Ended
	Mar. 31, 2017
Regulated Operations [Abstract]
Schedule Of Regulatory Assets And Liabilities

Fair Value (Tables)

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Schedule Of Face And Fair Value Of Debt	The following table shows the face value and the fair value of fixed-rate and variable-rate indebtedness (Level 2) for the periods ending: March 31, 2017 December 31, 2016 Face Value Fair Value Face Value Fair Value (In Millions) Fixed-rate $ 2,438.5 $ 2,564.3 $ 2,438.5 $ 2,543.5 Variable-rate 150.0 150.0 140.0 140.0 Total indebtedness $ 2,588.5 $ 2,714.3 $ 2,578.5 $ 2,683.5

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Schedule Long-Term Indebtedness	The following table presents our long-term debt: March 31, December 31, Series Due 2017 2016 (In Thousands) IPL first mortgage bonds: 5.40% (1) August 2017 $ 24,650 $ 24,650 3.875% (2) August 2021 55,000 55,000 3.875% (2) August 2021 40,000 40,000 3.125% (2) December 2024 40,000 40,000 6.60% January 2034 100,000 100,000 6.05% October 2036 158,800 158,800 6.60% June 2037 165,000 165,000 4.875% November 2041 140,000 140,000 4.65% June 2043 170,000 170,000 4.50% June 2044 130,000 130,000 4.70% September 2045 260,000 260,000 4.05% May 2046 350,000 350,000 Unamortized discount – net (6,446 ) (6,477 ) Deferred financing costs (16,557 ) (16,736 ) Total IPL first mortgage bonds 1,610,447 1,610,237 IPL unsecured debt: Variable (3) December 2020 30,000 30,000 Variable (3) December 2020 60,000 60,000 Deferred financing costs (428 ) (456 ) Total IPL unsecured debt 89,572 89,544 Total Long-term Debt – IPL 1,700,019 1,699,781 Long-term Debt – IPALCO: 5.00% Senior Secured Notes May 2018 400,000 400,000 3.45% Senior Secured Notes July 2020 405,000 405,000 Unamortized discount – net (247 ) (273 ) Deferred financing costs (4,526 ) (5,018 ) Total Long-term Debt – IPALCO 800,227 799,709 Total Consolidated IPALCO Long-term Debt 2,500,246 2,499,490 Less: Current Portion of Long-term Debt 24,650 24,650 Net Consolidated IPALCO Long-term Debt $ 2,475,596 $ 2,474,840 (1) First mortgage bonds are issued to the city of Petersburg, Indiana, to secure the loan proceeds from various tax-exempt bonds issued by the city. (2) First mortgage bonds are issued to the Indiana Finance Authority, to secure the loan of proceeds from tax-exempt bonds issued by the Indiana Finance Authority. (3) Unsecured notes are issued to the Indiana Finance Authority by IPL to facilitate the loan of proceeds from various tax-exempt notes issued by the Indiana Finance Authority. The notes have a final maturity date of December 2038, but are subject to a mandatory put in December 2020.

Benefit Plans (Tables)

Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2017
Compensation and Retirement Disclosure [Abstract]
Schedule Of Defined Benefit Plans Disclosures	The following table (in thousands) presents information for the three months ended March 31, 2017 , relating to the Pension Plans: Net unfunded status of plans: Net unfunded status at December 31, 2016, before tax adjustments $ (57,395 ) Net benefit cost components reflected in net unfunded status during first quarter: Service cost (1,836 ) Interest cost (6,327 ) Expected return on assets 11,167 Actuarial valuation adjustment 80 Employer contributions 7,211 Net unfunded status at March 31, 2017, before tax adjustments $ (47,100 ) Regulatory assets related to pensions (1) : Regulatory assets at December 31, 2016, before tax adjustments $ 223,705 Amount reclassified through net benefit cost: Amortization of prior service cost (1,060 ) Amortization of net actuarial loss (3,300 ) Settlements (2) (146 ) Actuarial valuation adjustment (80 ) Regulatory assets at March 31, 2017, before tax adjustments $ 219,119 (1) Amounts that would otherwise be charged/credited to Accumulated Other Comprehensive Income or Loss upon application of ASC 715, “Compensation – Retirement Benefits,” are recorded as a regulatory asset or liability because IPL has historically recovered and currently recovers pension and other postretirement benefit expenses in rates. These are unrecognized amounts not yet recognized as components of net periodic benefit costs. (2) The settlement loss of $0.1 million for the three months ended March 31, 2017 was the result of a lump sum distribution paid out of the Supplemental Retirement Plan.
Schedule Of Net Periodic Benefit Costs	The following table presents net periodic benefit cost information relating to the Pension Plans combined: For the Three Months Ended, March 31, 2017 2016 (In Thousands) Components of net periodic benefit cost: Service cost $ 1,836 $ 1,754 Interest cost 6,327 6,454 Expected return on plan assets (11,167 ) (10,873 ) Amortization of prior service cost 1,060 1,296 Amortization of actuarial loss 3,300 3,474 Settlements 146 — Net periodic benefit cost $ 1,502 $ 2,105

Overview and Summary of Signi21

Overview and Summary of Significant Accounting Policies (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)generating_stationmiMW	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
Distance of furthest customer from Indianapolis | mi	40
Number of generating stations | generating_station	4
Deferred financing costs | $	$ 21,500	$ 22,200
Adjustments for New Accounting Pronouncement [Member]
Debt Instrument [Line Items]
Deferred financing costs | $		(20,800)
Aes U.S. Investments [Member]
Debt Instrument [Line Items]
Ownership percentage by parent (percent)	82.40%
CDPQ [Member]
Debt Instrument [Line Items]
Ownership percentage by parent (percent)	17.70%
Ownership interest in parent company (percent)	15.00%
Percentage of direct and indirect ownership share of IPALCO	30.00%
AES U.S. Holdings, LLC [Member]
Debt Instrument [Line Items]
Ownership interest in parent company (percent)	85.00%
Indianapolis Power And Light Company [Member]
Debt Instrument [Line Items]
Electric generation capability for winter, megawatts | MW	2,996
Electric generation capability for summer, megawatts | MW	2,881
Deferred financing costs | $	$ 16,557	16,736
Deferred Debits [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Deferred financing costs | $		$ 300
Harding Street [Member]
Debt Instrument [Line Items]
Amount of New Operation for Battery Storage Unit, megawatts | MW	20
Eagle Valley [Member]
Debt Instrument [Line Items]
Expected CCGT Output, megawatts | MW	671

Regulatory Matters (Details)

Regulatory Matters (Details) $ in Thousands	1 Months Ended		3 Months Ended
	Mar. 31, 2016USD ($)	May 31, 2014MW	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Regulatory Matters [Line Items]
Approved increase to basic rates and charges	$ 30,800
Wholesale sales margins, percent shared with customers	50.00%
Total current regulatory assets			$ 32,040	$ 33,912
Total long-term regulatory assets			444,209	450,710
Total current regulatory liabilities			4,829	7,704
Total long-term regulatory liabilities			$ 676,676	$ 670,294
Benchmark for Wholesale Sales Margin	$ 6,300
Capacity Sales, Percent Shared with Customers	50.00%
Deferred fuel [Member]
Regulatory Matters [Line Items]
Regulatory liability recovery period			1 year
FTRs [Member]
Regulatory Matters [Line Items]
Regulatory liability recovery period			1 year
DSM program costs [Member]
Regulatory Matters [Line Items]
Regulatory liability recovery period			1 year
Environmental projects [Member]
Regulatory Matters [Line Items]
Regulatory asset recovery period			1 year
Deferred MISO Non-fuel Costs [Member]
Regulatory Matters [Line Items]
Total current regulatory assets			$ 11,767
Regulatory asset recovery period			1 year
Other miscellaneous [Member]
Regulatory Matters [Line Items]
Regulatory asset recovery period			1 year
Deferred MISO Costs [Member]
Regulatory Matters [Line Items]
Total regulatory assets			$ 117,700
LT - Other Miscellaneous [Member]
Regulatory Matters [Line Items]
Regulatory asset recovery period			2 years
Eagle Valley [Member]
Regulatory Matters [Line Items]
Public Utilities, Approved Production Plant Capacity, Minimum | MW		644
Public Utilities, Approved Production Plan Capacity , Maximum | MW		685
Increase to Annual Depreciation Rate [Member]
Regulatory Matters [Line Items]
Approved increase to basic rates and charges	$ 24,300

Fair Value (Narrative) (Details

Fair Value (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Asset retirement obligations	$ 80,754	$ 80,568
Unamortized deferred financing costs	21,500	22,200
Unamortized debt discount	$ 6,700	$ 6,800

Fair Value (Schedule Of Face An

Fair Value (Schedule Of Face And Fair Value Of Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Face Value	$ 2,588.5	$ 2,578.5
Fair Value	2,714.3	2,683.5
Fixed Rate [Member]
Debt Instrument [Line Items]
Face Value	2,438.5	2,438.5
Fair Value	2,564.3	2,543.5
Variable Rate [Member]
Debt Instrument [Line Items]
Face Value	150	140
Fair Value	$ 150	$ 140

Equity (Details)

Equity (Details) - USD ($) $ in Millions	Jun. 01, 2016	Mar. 01, 2016	Mar. 31, 2017
Common Stock [Member]
Class of Stock [Line Items]
Number of shares issued and sold (shares)		7,403,213
Value of shares issued and sold		$ 134.3
CDPQ [Member]
Class of Stock [Line Items]
Percentage of direct and indirect ownership share of IPALCO			30.00%
Parent Company [Member]
Class of Stock [Line Items]
Proceeds from Contributions from Parent	$ 64.8
Shareholder [Member]
Class of Stock [Line Items]
Proceeds from Contributed Capital	$ 13.9

Debt (Schedule Long-Term Indebt

Debt (Schedule Long-Term Indebtedness) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Unamortized discount - net	$ (6,700)	$ (6,800)
Deferred financing costs	(21,500)	(22,200)
Long-term debt	2,500,246	2,499,490
Less: Current Portion of Long-term Debt	24,650	24,650
Net Consolidated IPALCO Long-term Debt	2,475,596	2,474,840
Indianapolis Power And Light Company [Member]
Debt Instrument [Line Items]
First mortgage bonds	1,610,447	1,610,237
Unamortized discount - net	(6,446)	(6,477)
Deferred financing costs	(16,557)	(16,736)
Long-term debt	1,700,019	1,699,781
Unsecured Debt	$ 89,572	89,544
Indianapolis Power And Light Company [Member] | First Mortgage Bond 5.40% Due August 2017 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	5.40%
Debt due date	Aug. 1, 2017
First mortgage bonds	$ 24,650	24,650
Indianapolis Power And Light Company [Member] | First Mortgage Bond 3.875% Due August 2021 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	3.875%
Debt due date	Aug. 1, 2021
First mortgage bonds	$ 55,000	55,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 3.875% Due August 2021 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	3.875%
Debt due date	Aug. 1, 2021
First mortgage bonds	$ 40,000	40,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 4.55% Due December 2024 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.55%
Debt due date	Dec. 1, 2024
First mortgage bonds	$ 40,000	40,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 6.60% Due January 2034 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	6.60%
Debt due date	Jan. 1, 2034
First mortgage bonds	$ 100,000	100,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 6.05% Due October 2036 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	6.05%
Debt due date	Oct. 1, 2036
First mortgage bonds	$ 158,800	158,800
Indianapolis Power And Light Company [Member] | First Mortgage Bond 6.60% Due June 2037 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	6.60%
Debt due date	Jun. 1, 2037
First mortgage bonds	$ 165,000	165,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 4.875% Due November 2041 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.875%
Debt due date	Nov. 1, 2041
First mortgage bonds	$ 140,000	140,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 4.65% Due June 2043 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.65%
Debt due date	Jun. 1, 2043
First mortgage bonds	$ 170,000	170,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 4.50% Due June 2044[Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.50%
Debt due date	Jun. 1, 2044
First mortgage bonds	$ 130,000	130,000
Indianapolis Power And Light Company [Member] | First Mortgage Bond 4.70%, Due September 2045 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.70%
Debt due date	Sep. 1, 2045
First mortgage bonds	$ 260,000	260,000
Indianapolis Power And Light Company [Member] | FMB Twenty [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.05%
Debt due date	May 1, 2046
First mortgage bonds	$ 350,000	350,000
Indianapolis Power And Light Company [Member] | Environmental Facilities Refunding Revenue Notes, Series 2015A [Member]
Debt Instrument [Line Items]
Debt due date	Dec. 22, 2020
Unsecured Debt	$ 30,000	30,000
Indianapolis Power And Light Company [Member] | Environmental Facilities Refunding Revenue Notes, Series 2015B [Member]
Debt Instrument [Line Items]
Debt due date	Dec. 22, 2020
Unsecured Debt	$ 60,000	60,000
Ipalco Enterprises, Inc. [Member]
Debt Instrument [Line Items]
Unamortized discount - net	(247)	(273)
Deferred financing costs	(4,526)	(5,018)
Net Consolidated IPALCO Long-term Debt	$ 800,227	799,709
Ipalco Enterprises, Inc. [Member] | 5.00% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	5.00%
Debt due date	May 1, 2018
First mortgage bonds	$ 400,000
Long-term debt	400,000	400,000
Ipalco Enterprises, Inc. [Member] | Seven Point Two Five Percent Senior Secured Notes [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 400,000
Ipalco Enterprises, Inc. [Member] | 3.45% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	3.45%
Debt due date	Jul. 1, 2020
Long-term debt	$ 405,000	405,000
Unsecured Debt [Member] | Indianapolis Power And Light Company [Member]
Debt Instrument [Line Items]
Deferred financing costs	$ (428)	$ (456)

Debt (Narrative) (Details)

Debt (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended
	May 31, 2014	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Line of credit facility, term	5 years
Maximum borrowing capacity	$ 250,000,000
Line of credit facility, accordion feature	$ 150,000,000
Line of credit, outstanding borrowings		$ 60,000,000	$ 50,000,000
Letter of Credit [Member]
Debt Instrument [Line Items]
Debt instrument, maturity date		Oct. 16, 2020
Parent Company [Member] | Seven Point Two Five Percent Senior Secured Notes [Member]
Debt Instrument [Line Items]
Secured Debt		$ 400,000,000

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
State and federal income tax rate	31.80%	32.70%

Benefit Plans (Narrative) (Deta

Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Postretirement Health Care Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Unfunded obligation	$ 7	$ 6.8

Benefit Plans (Schedule Of Defi

Benefit Plans (Schedule Of Defined Benefit Plans Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net Unfunded Status of Plans [Roll Forward]
Net funded status before tax adjustments	$ (57,395)
Service cost	(1,836)	$ (1,754)
Interest cost	(6,327)	(6,454)
Expected return on assets	11,167	10,873
Defined Benefit Plan, Actuarial Gain (Loss)	(80)
Employer contributions	7,211
Net funded status before tax adjustments	(47,100)
Regulatory Assets Related to Pensions [Roll Forward]
Amortization of prior service cost	(1,060)	(1,296)
Defined Benefit Plan, Amortization of Gains (Losses)	(3,300)	(3,474)
Defined Benefit Plan, Settlements, Benefit Obligation	146	$ 0
Pension Plan [Member]
Net Unfunded Status of Plans [Roll Forward]
Defined Benefit Plan, Actuarial Gain (Loss)	(80)
Regulatory Assets Related to Pensions [Roll Forward]
Regulatory assets before tax adjustments	223,705
Amortization of prior service cost	(1,060)
Regulatory assets before tax adjustments	219,119
Defined Benefit Plan, Amortization of Gains (Losses)	(3,300)
Defined Benefit Plan, Settlements, Benefit Obligation	$ 146

Benefit Plans (Schedule Of Net

Benefit Plans (Schedule Of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 1,836	$ 1,754
Interest cost	6,327	6,454
Expected return on assets	(11,167)	(10,873)
Amortization of prior service cost	1,060	1,296
Amortization of actuarial loss	3,300	3,474
Defined Benefit Plan, Settlements, Benefit Obligation	146	0
Net periodic benefit cost	$ 1,502	$ 2,105

Commitments and Contingencies (

Commitments and Contingencies (Details)	1 Months Ended
	Oct. 31, 2009coal_fired_electric_generating_facility
Indianapolis Power And Light Company [Member]
Entity Information [Line Items]
Number of facilities with violations of Federal Clean Air Act	3

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2016
Debt Instrument [Line Items]
Cash	$ 12,400			$ 8,300
Long-term nonutility investments	$ 4,800			$ 5,200
Nonutility assets representation rate (percentage, less than)	1.00%		1.00%
Net income	$ 26,996	$ 27,405
Utility Segment [Member]
Debt Instrument [Line Items]
Net income	$ 32,300	$ 33,600