WEC Energy (WEC) 10-Q 5 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - Jun. 30, 2015 - USD ($) $ in Billions	Total
Entity Information [Line Items]
Entity Registrant Name	WEC Energy Group, Inc.
Entity Central Index Key	783,325
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding	315,684,458
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float	$ 14.2

Consolidated Condensed Income S

Consolidated Condensed Income Statements (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Operating Revenues	$ 991.2	$ 1,043.7	$ 2,379.1	$ 2,738.7
Operating Expenses
Fuel and purchased power	273.7	292.5	571.4	611.1
Cost of gas sold	79.3	125.9	395.5	717.4
Other operation and maintenance	337	256	617.7	531.4
Depreciation and amortization	105.7	101.4	210.8	202
Property and revenue taxes	31.9	30.3	63.8	60.9
Total Operating Expenses	827.6	806.1	1,859.2	2,122.8
Treasury Grant	2.2	3.1	4.7	6.6
Operating Income	165.8	240.7	524.6	622.5
Equity in Earnings of Unconsolidated Affiliates	14.2	17.5	30.3	34.8
Other Income, net	26.1	8.1	29.1	9.2
Interest Expense, net	62.1	59	121.8	121.3
Income from Continuing Operations Before Income Taxes	144.1	207.3	462.3	545.2
Income Tax Expense	63.2	74.3	185.6	204.6
Net Income	$ 80.9	$ 133	$ 276.7	$ 340.6
Earnings Per Share (Basic)
Continuing operations	$ 0.36	$ 0.59	$ 1.22	$ 1.51
Earnings Per Share (Diluted)
Continuing operations	$ 0.35	$ 0.58	$ 1.21	$ 1.50
Weighted Average Common Shares Outstanding (Millions)
Basic	227.5	225.5	226.5	225.6
Diluted	229.1	227.6	228.2	227.7
Dividends Per Share of Common Stock	$ 0.8629
Transmission Affiliate [Member]
Operating Expenses
Equity in Earnings of Unconsolidated Affiliates	$ 14.3	$ 17.5	$ 30.4	$ 34.8

Consolidated Condensed Statemen

Consolidated Condensed Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$ 80.9	$ 133	$ 276.7	$ 340.6
Cash flow hedges
Realized gains, net of tax	11.4	0	11.4	0
Reclassification of net losses (gains) to net income	(0.1)	0	(0.1)	0
Total other comprehensive income	11.3	0	11.3	0
Comprehensive income attributed to common shareholders	$ 92.2	$ 133	$ 288	$ 340.6

Consolidated Condensed Stateme4

Consolidated Condensed Statements of Comprehensive Income (Unaudited) (parenthetical) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Realized gains, tax	$ 7.6	$ 0	$ 7.6	$ 0

Consolidated Condensed Balance

Consolidated Condensed Balance Sheets (Unaudited) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment
In service	$ 25,447.9	$ 15,509
Accumulated depreciation	(7,857.4)	(4,485.1)
Property, Plant and Equipment in Service, Net	17,590.5	11,023.9
Construction work in progress	899.6	191.8
Leased facilities, net	39.3	42
Net Property, Plant and Equipment	18,529.4	11,257.7
Investments
Equity investment in transmission affiliate	987.8
Other	181.9	32.8
Total Investments	1,169.7	456.9
Current Assets
Cash and cash equivalents	214.4	61.9
Accounts receivable, net	667.5	352.1
Accrued revenues	289.1	291.3
Materials, supplies and inventories	562.5	400.6
Current deferred tax asset, net	236.4	242.7
Prepayments and other	306.9	186.8
Total Current Assets	2,276.8	1,535.4
Deferred Charges and Other Assets
Regulatory assets	2,796.4	1,271.2
Goodwill	3,386.5	441.9
Other	455.7	200.3
Total Deferred Charges and Other Assets	6,638.6	1,913.4
Total Assets	28,614.5	15,163.4
Capitalization
Common equity	8,456.7	4,419.7
Preferred stock of subsidiary	81.5	30.4
Long-term debt	8,547.6	4,186.4
Total Capitalization	17,085.8	8,636.5
Current Liabilities
Long-term debt due currently	608.4	424.1
Short-term debt	826.3	617.6
Accounts payable	777.1	363.3
Accrued payroll and benefits	135.7	95.1
Other	592.8	168.6
Total Current Liabilities	2,940.3	1,668.7
Deferred Credits and Other Liabilities
Regulatory liabilities	1,313	830.6
Deferred income taxes - long-term	4,624.3	2,906.7
Deferred revenue, net	596.2	614.1
Pension and other benefit obligations	428	203.8
Other	1,626.9	303
Total Deferred Credits and Other Liabilities	8,588.4	4,858.2
Total Capitalization and Liabilities	$ 28,614.5	$ 15,163.4

Consolidated Condensed Stateme6

Consolidated Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Operating Activities
Net Income	$ 276.7	$ 340.6
Reconciliation to cash
Depreciation and amortization	216.8	206.5
Deferred income taxes and investment tax credits, net	121.7	188
Contributions to qualified benefit plans	(100)	0
Change in -
Accounts receivable and accrued revenues	134.5	132
Inventories	72.2	25.1
Other current assets	16.7	11.8
Accounts payable	27.4	(52.6)
Accrued income taxes, net	10.5	(10.6)
Other current liabilities	(1.2)	(21.6)
Other, net	(59.4)	(97.9)
Cash Provided by Operating Activities	715.9	721.3
Investing Activities
Capital expenditures	(356.5)	(305.5)
Business acquisition, net of cash acquired of $156.3 million	(1,329.4)	0
Cash acquired from acquisition	156.3
Investment in transmission affiliate	(2.6)	(7.9)
Other, net	9.3	0.5
Cash Used in Investing Activities	(1,679.2)	(312.9)
Financing Activities
Exercise of stock options	12.2	17.6
Purchase of common stock	(32)	(57.3)
Dividends paid on common stock	(190.5)	(176)
Issuance of long-term debt	1,450	250
Retirement of long-term debt	(11.6)	(311.1)
Change in short-term debt	(105.7)	(127.3)
Other, net	(6.6)	3.1
Cash Provided by (Used in) Financing Activities	1,115.8	(401)
Change in Cash and Cash Equivalents	152.5	7.4
Cash and Cash Equivalents at Beginning of Period	61.9	26
Cash and Cash Equivalents at End of Period	$ 214.4	$ 33.4

General Information

General Information	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
GENERAL INFORMATION	GENERAL INFORMATION On June 29, 2015 , Wisconsin Energy Corporation acquired Integrys and the combined company was renamed WEC Energy Group, Inc. Our condensed consolidated balance sheet as of June 30, 2015 reflects the acquisition of Integrys. The condensed consolidated income statements, statements of comprehensive income, and statements of cash flows for the three and six-month periods ended June 30, 2015 do not include the results of the Integrys companies because they were immaterial due to the timing of the closing of the acquisition. We will include the Integrys companies in our operating results for periods subsequent to June 30, 2015. Our accompanying unaudited consolidated condensed financial statements should be read in conjunction with Item 8. Financial Statements and Supplementary Data, in our 2014 Annual Report on Form 10-K. In the opinion of management, we have included all adjustments, normal and recurring in nature, necessary for a fair presentation of the results of operations, cash flows and financial position in the accompanying income statements, statements of comprehensive income, statements of cash flows and balance sheets. The results of operations for the three and six months ended June 30, 2015 are not necessarily indicative of the results which may be expected for the entire fiscal year 2015 because of the acquisition of Integrys, seasonal and other factors.

Acquisition

Acquisition	6 Months Ended
	Jun. 30, 2015
Business Combinations [Abstract]
Mergers, Acquisitions and Dispositions Disclosures [Text Block]	ACQUISITION On June 29, 2015 , Wisconsin Energy acquired 100% of the outstanding common shares of Integrys, a provider of regulated natural gas and electricity, as well as nonregulated renewable energy and compressed natural gas products and services. Integrys also held a 34% interest in ATC, a for-profit transmission company regulated by the Federal Energy Regulatory Commission (FERC). The acquisition of Integrys provides increased access to scale, the potential for long-term cost savings through a combination of lower capital and operating costs, and the potential for operating efficiencies . Pursuant to the Merger Agreement, Integrys’ shareholders received 1.128 shares of Wisconsin Energy common stock and $18.58 in cash per Integrys share of common stock. The total consideration transferred was based on the closing price of Wisconsin Energy common stock on June 29, 2015 , and was calculated as follows: Stock Cash Total (Millions of Dollars, except per share amounts) Integrys common shares outstanding at June 29, 2015 79,963,091 79,963,091 Exchange ratio 1.128 Wisconsin Energy shares issued for Integrys shares (a) 90,187,884 Closing price of Wisconsin Energy common shares on June 29, 2015 $45.16 Fair value of common stock issued $ 4,072.9 $ 4,072.9 Cash paid per share of Integrys shares outstanding $18.58 Fair value of cash paid for Integrys shares (a) $ 1,486.2 $ 1,486.2 Consideration attributable to settlement of equity awards, net of tax $ 24.0 $ 24.0 Total purchase price $ 4,072.9 $ 1,510.2 $ 5,583.1 (a) 10,483 fractional shares totaling $0.5 million were paid in cash. All Integrys unvested stock-based compensation awards became fully vested upon the close of the transaction and were either paid to award recipients in cash, or the value of the awards was deferred into a deferred compensation plan. In addition, all vested but unexercised Integrys stock options were paid in cash. In accordance with accounting guidance for business combinations, the expense caused by the acceleration of the vesting was an expense related to the transaction. The Integrys assets acquired and the liabilities assumed were measured at estimated fair value as defined in the accounting guidance. Substantially all of Integrys' operations are subject to the rate-setting authority of federal and state regulatory commissions. These operations are accounted for in accordance with GAAP accounting guidance for regulated operations. In addition, the underlying assets and liabilities of ATC are regulated by FERC. The fair values of Integrys' assets and liabilities subject to these rate-setting provisions approximate their carrying values, and the assets and liabilities acquired and pro forma financial information do not reflect any net adjustments related to these amounts. The excess of the purchase price over the estimated fair values of the assets acquired and liabilities assumed was recognized as goodwill. The goodwill reflects the value paid for the increased access to scale and efficiencies as a result of the combination. The goodwill recognized is not deductible for income tax purposes, and as such no deferred taxes have been recorded related to goodwill. The preliminary purchase price allocation of the acquisition was as follows: (Millions of Dollars) Current assets $ 1,178.2 Net property, plant and equipment 7,098.2 Goodwill 2,944.6 Deferred charges and other assets, excluding goodwill 2,410.5 Current liabilities, including current maturities of long-term debt (1,260.1 ) Deferred credits and other liabilities (3,769.6 ) Long-term debt (2,967.6 ) Preferred stock of subsidiary (51.1 ) Total purchase price $ 5,583.1 The allocation of goodwill to the reporting segments has not yet been determined, due to the short time frame between the acquisition close date and the issuing date of this report. The acquisition was subject to the approvals of various government agencies, including the FERC, Federal Communications Commission (FCC), Public Service Commission of Wisconsin (PSCW), Illinois Commerce Commission (ICC), Michigan Public Service Commission (MPSC), and Minnesota Public Utilities Commission (MPUC). Approvals were obtained from all agencies subject to several conditions. The PSCW order included the following conditions: • Wisconsin Electric and Wisconsin Gas will be subject to an earnings sharing mechanism for three years beginning January 1, 2016. Under the earnings sharing mechanism, any additional earnings over the authorized rate of return will be shared with ratepayers. • Any future electric generation projects affecting Wisconsin ratepayers submitted by WEC Energy Group or its subsidiaries will first consider the extent to which existing intercompany resources can meet energy and capacity needs. Additionally, the ICC order included a base rate freeze for The Peoples Gas Light and Coke Company (PGL) and North Shore Gas Company (NSG) effective for two years after the close of the acquisition. We do not believe that the conditions set forth in the various regulatory orders approving the acquisition will have a material impact on operations or financial results. The following unaudited pro forma financial information reflects the consolidated results and amortization of purchase price adjustments as if the acquisition had taken place on January 1, 2014. The unaudited pro forma financial information is presented for illustrative purposes only and is not necessarily indicative of the consolidated results of operations that would have been achieved or the future consolidated results of WEC Energy Group. The pro forma financial information does not reflect any potential cost savings from operating efficiencies resulting from the transaction and does not include transaction costs related to the acquisition. The information is preliminary in nature and subject to change. After-tax transaction costs incurred were $53.9 million ( $0.24 per share) and $62.3 million ( $0.28 per share) for the three and six months ended June 30, 2015, respectively, and $3.0 million ( $0.01 per share) for both the three and six months ended June 30, 2014, which were recorded primarily in Other Operation and Maintenance expense. Unaudited Pro Forma Financial Information Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars, Except Per Share Amounts) Operating Revenues $ 1,629.2 $ 1,879.5 $ 4,180.1 $ 5,208.2 Net Income $ 159.1 $ 143.2 $ 488.7 $ 499.5 Earnings per share (Basic) $ 0.50 $ 0.46 $ 1.55 $ 1.54 Earnings per share (Diluted) $ 0.50 $ 0.45 $ 1.54 $ 1.53 As a result of the acquisition, our ownership of ATC increased to approximately 60% . We have made commitments with respect to our voting rights of the combined ownership of ATC, which are included as enforceable conditions in the orders approving the transaction by the FERC and the PSCW. We also expect that ATC's governance documents will include these voting commitments. Under GAAP, these commitments do not allow for the consolidation of ATC in our financial statements and the 60% ownership is accounted for as an equity method investment subsequent to the close of the transaction. See Note 11 -- Investment in ATC in the Notes to Consolidated Condensed Financial Statements.

Common Equity

Common Equity	6 Months Ended
	Jun. 30, 2015
Stockholders' Equity Note [Abstract]
COMMON EQUITY	COMMON EQUITY Stock Option Activity: The following table identifies non-qualified stock options granted by the Compensation Committee of the Board of Directors (Compensation Committee): 2015 2014 Non-qualified stock options granted year to date 516,475 899,500 Estimated fair value per non-qualified stock option $ 5.29 $ 4.18 Assumptions used to value the options using a binomial option pricing model: Risk-free interest rate 0.1% - 2.1% 0.1% - 3.0% Dividend yield 3.7 % 3.8 % Expected volatility 18.0 % 18.0 % Expected forfeiture rate 2.0 % 2.0 % Expected life (years) 5.8 5.8 The risk-free interest rate is based on the U.S. Treasury interest rate whose term is consistent with the expected life of the stock options. Dividend yield, expected volatility, expected forfeiture rate and expected life assumptions are based on our historical experience. The following is a summary of our stock option activity for the three and six months ended June 30, 2015 : Weighted- Average Weighted- Remaining Aggregate Number of Average Contractual Life Intrinsic Value Stock Options Options Exercise Price (Years) (Millions) Outstanding as of April 1, 2015 6,927,549 $ 32.04 Granted — $ — Exercised (176,619 ) $ 21.10 Forfeited — $ — Outstanding as of June 30, 2015 6,750,930 $ 32.32 Outstanding as of January 1, 2015 6,770,194 $ 29.99 Granted 516,475 $ 52.90 Exercised (535,739 ) $ 22.73 Forfeited — $ — Outstanding as of June 30, 2015 6,750,930 $ 32.32 5.7 $ 85.4 Exercisable as of June 30, 2015 4,014,465 $ 26.06 4.0 $ 75.9 The intrinsic value of options exercised was $4.8 million and $15.4 million for the three and six months ended June 30, 2015 and $2.2 million and $17.5 million for the same periods in 2014 , respectively. Cash received from options exercised was $12.2 million and $17.6 million for the six months ended June 30, 2015 and 2014 , respectively. The actual tax benefit realized for the tax deductions from option exercises for the same periods was $6.2 million and $7.0 million , respectively. Stock options to purchase 516,475 shares of common stock with an exercise price of $52.90 were outstanding during the second quarter of 2015 , but were not included in the computation of diluted earnings per share because they were anti-dilutive. The following table summarizes information about stock options outstanding as of June 30, 2015 : Options Outstanding Options Exercisable Weighted-Average Weighted-Average Remaining Remaining Number of Exercise Contractual Number of Exercise Contractual Range of Exercise Prices Options Price Life (Years) Options Price Life (Years) $19.74 to $21.11 1,236,412 $ 20.98 3.2 1,236,412 $ 20.98 3.2 $23.88 to $29.35 1,897,488 $ 25.15 3.3 1,897,488 $ 25.15 3.3 $34.88 to $52.90 3,617,030 $ 39.96 7.8 880,565 $ 35.15 6.6 6,750,930 $ 32.32 5.7 4,014,465 $ 26.06 4.0 The following table summarizes information about our non-vested options during the three and six months ended June 30, 2015 : Weighted-Average Non-Vested Stock Options Number of Options Fair Value Non-vested as of April 1, 2015 2,736,465 $ 4.03 Granted — $ — Vested — $ — Forfeited — $ — Non-vested as of June 30, 2015 2,736,465 $ 4.03 Non-vested as of January 1, 2015 2,879,855 $ 3.65 Granted 516,475 $ 5.29 Vested (659,865 ) $ 3.34 Forfeited — $ — Non-vested as of June 30, 2015 2,736,465 $ 4.03 As of June 30, 2015 , total compensation costs related to non-vested stock options not yet recognized was approximately $3.2 million , which is expected to be recognized over the next 18 months on a weighted-average basis. Restricted Shares: The following restricted stock activity occurred during the three and six months ended June 30, 2015 : Weighted-Average Restricted Shares Number of Shares Grant Date Fair Value Outstanding as of April 1, 2015 147,214 Granted — $ — Released — $ — Forfeited — $ — Outstanding as of June 30, 2015 147,214 Outstanding as of January 1, 2015 155,479 Granted 60,164 $ 53.83 Released (68,429 ) $ 36.95 Forfeited — $ — Outstanding as of June 30, 2015 147,214 We record the market value of the restricted stock awards on the date of grant, and then we charge their value to expense over the vesting period of the awards. The intrinsic value of restricted stock vesting was zero and $3.7 million for the three and six months ended June 30, 2015 , and zero and $2.7 million for the same periods in 2014 , respectively. The actual tax benefit realized for the tax deductions from released restricted shares was zero and $1.3 million for the three and six months ended June 30, 2015 , and zero and $1.0 million for the same periods in 2014 , respectively. As of June 30, 2015 , total compensation cost related to restricted stock not yet recognized was approximately $4.6 million , which is expected to be recognized over the next 24 months on a weighted-average basis. Performance Units: In January 2015 and 2014 , the Compensation Committee granted 195,365 and 233,735 performance units, respectively, to officers and other key employees under the Wisconsin Energy Performance Unit Plan. Performance units earned as of December 31, 2014 and 2013 vested and were settled during the first quarter of 2015 and 2014 , and had a total intrinsic value of $13.2 million and $14.8 million , respectively. The actual tax benefit realized for the tax deductions from the settlement of performance units was approximately $4.8 million and $5.3 million , respectively. As of June 30, 2015 , total compensation cost related to performance units not yet recognized was approximately $14.2 million , which is expected to be recognized over the next 23 months on a weighted-average basis. Restrictions: Our ability as a holding company to pay common dividends primarily depends on the availability of funds received from our non-utility subsidiary, We Power, and our utility subsidiaries. Various financing arrangements and regulatory requirements impose certain restrictions on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans or advances. All utility subsidiaries, with the exception of Michigan Gas Utilities Corporation (MGU), are prohibited from loaning funds to us, either directly or indirectly. The PSCW allows Wisconsin Public Service Corporation (WPS) to pay dividends on its common stock of no more than 103% of the previous year’s common stock dividend. WPS may return capital to us if its average financial common equity ratio is at least 51% on a calendar-year basis. WPS must obtain PSCW approval if a return of capital would cause its average financial common equity ratio to fall below this level. Our right to receive dividends on the common stock of WPS is also subject to the prior rights of WPS' preferred shareholders and to provisions in WPS' restated articles of incorporation, which limit the amount of common stock dividends that WPS may pay if its common stock and common stock surplus accounts constitute less than 25% of its total capitalization. Integrys has short-term and long-term debt obligations that contain financial and other covenants, including but not limited to, a requirement to maintain a debt to total capitalization ratio not to exceed 65% . NSG's long-term debt obligations contain provisions and covenants restricting the payment of cash dividends and the purchase or redemption of its capital stock. PGL and WPS have short-term debt obligations containing financial and other covenants, including but not limited to, a requirement to maintain a debt to total capitalization ratio not to exceed 65% . See Note H -- Common Equity in our 2014 Annual Report on Form 10-K for additional information on restrictions at our other subsidiaries. We do not believe that these restrictions will materially affect our operations or limit any dividend payments in the foreseeable future. Share Repurchase Program: In December 2013, our Board of Directors authorized a share repurchase program for the purchase of up to $300 million of our common stock through open market purchases or privately negotiated transactions from January 1, 2014 through the end of 2017. On June 22, 2014, in connection with the proposed acquisition of Integrys, the Board of Directors terminated this share repurchase program. In addition, we have instructed our independent agents to purchase shares on the open market to fulfill exercised stock options and restricted stock awards. The following table identifies shares purchased in the following periods: Six Months Ended June 30 2015 2014 Shares Cost Shares Cost (In Millions) Under share repurchase program — $ — 0.4 $ 18.6 To fulfill exercised stock options and restricted stock awards 0.6 32.0 0.9 38.7 Total 0.6 $ 32.0 1.3 $ 57.3

Long Term Debt

Long Term Debt	6 Months Ended
	Jun. 30, 2015
Long-term Debt, Unclassified [Abstract]
LONG TERM DEBT	LONG-TERM DEBT Our outstanding long-term debt, including current maturities as of June 30, 2015 , includes approximately $3.1 billion of Integrys debt assumed on June 29, 2015. This amount includes $45.7 million of fair value adjustments recorded in connection with purchase accounting, which will be amortized over the estimated remaining life of the debt and will not be a part of future principal payments. For additional information on the acquisition, see Note 2 -- Acquisition in the Notes to Consolidated Condensed Financial Statements. In June 2015, WEC Energy Group issued $300 million of 1.65% Senior Notes due June 15, 2018, $400 million of 2.45% Senior Notes due June 15, 2020, and $500 million of 3.55% Senior Notes due June 15, 2025. The net proceeds were used to pay the cash consideration for the acquisition of Integrys and related transaction costs, and for general corporate purposes. In July 2015 , Integrys tendered an offer to repurchase all $55.0 million outstanding of its 8.00% Senior Notes due June 1, 2016. The $55.0 million balance of these notes was included in the current portion of long-term debt on our balance sheet at June 30, 2015. In May 2015, Wisconsin Electric issued $250 million of 3.10% Debentures due June 1, 2025. The net proceeds were used to repay short-term debt and for general corporate purposes. In May 2014, Wisconsin Electric issued $250 million of 4.25% Debentures due June 1, 2044. The net proceeds were used to repay short-term debt and for general corporate purposes. On April 1, 2014, Wisconsin Electric used short-term borrowings to retire $300 million of long-term debt that matured.

Materials, Supplies and Invento

Materials, Supplies and Inventories	6 Months Ended
	Jun. 30, 2015
Inventory Disclosure [Abstract]
Materials, Supplies and Inventories	MATERIALS, SUPPLIES AND INVENTORIES Our inventory consists of: Materials, Supplies and Inventories June 30, 2015 December 31, 2014 (Millions of Dollars) Fossil Fuel $ 182.4 $ 125.6 Materials and Supplies 249.7 150.2 Natural Gas in Storage 130.4 124.8 Total $ 562.5 $ 400.6 Substantially all fossil fuel, materials and supplies, and natural gas in storage inventories are recorded using the weighted-average cost method of accounting. PGL and NSG price natural gas storage injections at the calendar year average of the costs of natural gas supply purchased. Withdrawals from storage are priced on the Last-in, First-out (LIFO) cost method. For interim periods, the difference between current projected replacement cost and the LIFO cost for quantities of natural gas temporarily withdrawn from storage is recorded as a temporary LIFO liquidation debit or credit. The amounts as of June 30, 2015 were as follows: As of June 30, 2015 Balance Sheet Presentation PGL NSG (Millions of Dollars) Temporary LIFO liquidation debit Other current assets $ 21.0 $ — Temporary LIFO liquidation credit Other current Liabilities $ — $ 5.2 Due to seasonality requirements, PGL and NSG expect these interim reductions in LIFO layers to be replenished by year end.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2015
Fair Value Measurements [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Fair value measurements require enhanced disclosures about assets and liabilities that are measured and reported at fair value and establish a hierarchal disclosure framework which prioritizes and ranks the level of observable inputs used in measuring fair value. Fair value is the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). We primarily apply the market approach for recurring fair value measurements and attempt to utilize the best available information. Accordingly, we also utilize valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. We are able to classify fair value balances based on the observability of those inputs. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). Assets and liabilities measured and reported at fair value are classified and disclosed in one of the following categories: Level 1 -- Pricing inputs are unadjusted quoted prices available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Instruments in this category consist of financial instruments such as exchange-traded derivatives, cash equivalents and restricted cash investments. Level 2 -- Pricing inputs are other than quoted prices in active markets, which are either directly or indirectly observable as of the reporting date, and fair value is determined through the use of models or other valuation methodologies. Instruments in this category include non-exchange-traded derivatives such as Over-the-Counter (OTC) forwards and options. Level 3 -- Pricing inputs include significant inputs that are generally less observable from objective sources. The inputs in the determination of fair value require significant management judgment or estimation. At each balance sheet date, we perform an analysis of all instruments subject to fair value reporting and include in Level 3 all instruments whose fair value is based on significant unobservable inputs. In certain cases, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, an instrument's level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the instrument. The following tables summarize our financial assets and liabilities by level within the fair value hierarchy: Recurring Fair Value Measures As of June 30, 2015 Level 1 Level 2 Level 3 Total (Millions of Dollars) Assets: Derivatives $ 3.5 $ 4.1 $ 7.7 $ 15.3 Total $ 3.5 $ 4.1 $ 7.7 $ 15.3 Liabilities: Derivatives $ 6.7 $ 26.6 $ 5.4 $ 38.7 Total $ 6.7 $ 26.6 $ 5.4 $ 38.7 Recurring Fair Value Measures As of December 31, 2014 Level 1 Level 2 Level 3 Total (Millions of Dollars) Assets: Derivatives $ 1.1 $ 7.2 $ 7.0 $ 15.3 Total $ 1.1 $ 7.2 $ 7.0 $ 15.3 Liabilities: Derivatives $ 11.5 $ 1.0 $ — $ 12.5 Total $ 11.5 $ 1.0 $ — $ 12.5 Derivatives reflect positions we hold in exchange-traded derivative contracts and OTC derivative contracts. Exchange-traded derivative contracts, which include futures and exchange-traded options, are generally based on unadjusted quoted prices in active markets and are classified within Level 1. Some OTC derivative contracts are valued using broker or dealer quotations, or market transactions in either the listed or OTC markets utilizing a mid-market pricing convention (the mid-point between bid and ask prices), as appropriate. In such cases, these derivatives are classified within Level 2. Certain OTC derivatives may utilize models to measure fair value. Generally, we use a similar model to value similar instruments. Valuation models utilize various inputs which include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, other observable inputs for the asset or liability, and market-corroborated inputs (i.e., inputs derived principally from or corroborated by observable market data by correlation or other means). Where observable inputs are available for substantially the full term of the asset or liability, the instrument is categorized in Level 2. Certain OTC derivatives are in less active markets with a lower availability of pricing information which might not be observable in or corroborated by the market. When such inputs have a significant impact on the measurement of fair value, the instrument is categorized in Level 3. The following table summarizes the changes to derivatives classified as Level 3 in the fair value hierarchy: Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars) Beginning Balance $ 3.3 $ 1.7 $ 7.0 $ 3.5 Realized and unrealized gains (losses) — — — — Purchases 3.9 15.6 3.9 15.6 Issuances — — — — Settlements (3.6 ) (3.2 ) (7.3 ) (5.0 ) Acquisition of Integrys (1.3 ) — (1.3 ) — Transfers in and/or out of Level 3 — — — — Balance as of June 30 $ 2.3 $ 14.1 $ 2.3 $ 14.1 Derivative instruments reflected in Level 3 of the hierarchy include Midcontinent Independent System Operator, Inc. (MISO) Financial Transmission Rights (FTRs) that are measured at fair value each reporting period using monthly or annual auction shadow prices from relevant auctions. Changes in fair value for Level 3 recurring items are recorded on our balance sheet. See Note 7 -- Derivative Instruments in the Notes to Consolidated Condensed Financial Statements for further information on the offset to regulatory assets and liabilities. The carrying amount and estimated fair value of certain of our recorded financial instruments are as follows: June 30, 2015 December 31, 2014 Financial Instruments Carrying Amount Fair Value Carrying Amount Fair Value (Millions of Dollars) Preferred stock, no redemption required $ 81.5 $ 80.1 $ 30.4 $ 27.1 Long-term debt, including current portion $ 9,118.4 $ 9,181.1 $ 4,552.4 $ 5,126.0 The carrying value of net accounts receivable, accounts payable and short-term borrowings approximates fair value due to the short-term nature of these instruments. The fair value of our preferred stock is estimated based upon the quoted market value for the same or similar issues. The fair value of our long-term debt, including the current portion of long-term debt, but excluding capitalized leases and unamortized discount on debt, is estimated based upon quoted market value for the same or similar issues or upon the quoted market prices of U.S. Treasury issues having a similar term to maturity, adjusted for the issuing company's bond rating and the present value of future cash flows.

Derivative Instruments

Derivative Instruments	6 Months Ended
	Jun. 30, 2015
Derivative Instruments and Hedges, Assets [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS We utilize derivatives as part of our risk management program to manage the volatility and costs of purchased power, generation and natural gas purchases for the benefit of our customers and shareholders. Our approach is non-speculative and designed to mitigate risk and protect against price volatility. Regulated hedging programs are approved, if required, by our state regulators. We record derivative instruments on the balance sheet as an asset or liability measured at its fair value, and changes in the derivative's fair value are recognized currently in earnings unless specific hedge accounting criteria are met or we receive regulatory treatment for the derivative. For most energy related physical and financial contracts in our regulated operations that qualify as derivatives, our regulators allow the effects of the fair market value accounting to be offset to regulatory assets and liabilities. As of June 30, 2015 , we recognized $49.8 million in regulatory assets and $21.6 million in regulatory liabilities related to derivatives in comparison to $14.7 million in regulatory assets and $14.2 million in regulatory liabilities as of December 31, 2014 . We record our current derivative assets on the balance sheet in Prepayments and other current assets and the current portion of the liabilities in Other current liabilities. The long-term portion of our derivative assets of $1.0 million is recorded in Other long-term assets as of June 30, 2015 , and the long-term portion of our derivative liabilities of $5.2 million is recorded in Other long-term liabilities as of June 30, 2015 . Our Consolidated Condensed Balance Sheets as of June 30, 2015 and December 31, 2014 include: June 30, 2015 December 31, 2014 Derivative Asset Derivative Liability Derivative Asset Derivative Liability (Millions of Dollars) Natural Gas $ 6.2 $ 26.9 $ 5.0 $ 12.3 Fuel Oil 0.1 0.9 — — FTRs 7.7 — 7.0 — Coal 1.3 10.9 3.3 0.2 Total $ 15.3 $ 38.7 $ 15.3 $ 12.5 Our Consolidated Condensed Income Statements include gains (losses) on derivative instruments used in our risk management strategies under fuel and purchased power for those commodities supporting our electric operations and under cost of gas sold for the natural gas sold to our customers. Our estimated notional volumes and gains (losses) were as follows: Three Months Ended June 30, 2015 Three Months Ended June 30, 2014 Volume Gains (Losses) Volume Gains (Losses) (Millions of Dollars) (Millions of Dollars) Natural Gas 10.0 million Dth $ (5.9 ) 9.9 million Dth $ 2.5 Fuel Oil 0.8 million gallons 0.1 2.4 million gallons 0.4 FTRs 5.9 million MWh 0.8 7.4 million MWh 2.6 Total $ (5.0 ) $ 5.5 Six Months Ended June 30, 2015 Six Months Ended June 30, 2014 Volume Gains (Losses) Volume Gains (Losses) (Millions of Dollars) (Millions of Dollars) Natural Gas 23.3 million Dth $ (13.0 ) 24.8 million Dth $ 10.1 Fuel Oil 1.7 million gallons — 4.4 million gallons 0.6 FTRs 12.1 million MWh 2.9 13.1 million MWh 9.6 Total $ (10.1 ) $ 20.3 The gains (losses) above do not include Integrys. As of June 30, 2015 and December 31, 2014 , we posted collateral of $26.3 million and $11.2 million , respectively, in our margin accounts. These amounts are recorded on the balance sheets in Prepayments and other current assets. The fair value amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral are not offset against the fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. The table below shows derivative assets and derivative liabilities if derivative instruments by counterparty were presented net on the balance sheet as of June 30, 2015 and December 31, 2014 : June 30, 2015 December 31, 2014 Derivative Derivative Derivative Derivative Asset Liability Asset Liability (Millions of Dollars) Gross Amount Recognized on the Balance Sheet $ 15.3 $ 38.7 $ 15.3 $ 12.5 Gross Amount Not Offset on Balance Sheet (a) (4.9 ) (8.9 ) (0.4 ) (11.5 ) Net Amount $ 10.4 $ 29.8 $ 14.9 $ 1.0 (a) Gross Amount Not Offset on Balance Sheet includes cash collateral posted of $3.9 million and $10.3 million as of June 30, 2015 and December 31, 2014 , respectively. During the second quarter of 2015, we settled several forward interest rate swap agreements entered into earlier in the quarter to mitigate interest risk associated with the issuance of $1.2 billion of long-term debt related to the acquisition of Integrys. As these agreements qualified for cash flow hedging accounting treatment, the payments of $19.0 million received upon settlement of these agreements are deferred in Accumulated other comprehensive income and will be amortized as a decrease to interest expense over the periods in which the interest costs are recognized in earnings. For the three months ended June 30, 2015, we reclassified $0.1 million in forward interest rate swap agreement settlements deferred in Accumulated other comprehensive income as a reduction to interest expense. We estimate that during the next twelve months, $1.3 million will be reclassified from Accumulated other comprehensive income as a reduction to interest expense.

Guarantees

Guarantees	6 Months Ended
	Jun. 30, 2015
Guarantees [Abstract]
GUARANTEES	GUARANTEES The following table shows our outstanding guarantees: Total Amounts Expiration Committed at Less Than 1 to 3 Over 3 June 30, 2015 1 Year Years Years (Millions of Dollars) Guarantees: Guarantees supporting commodity transactions of subsidiaries (a) $ 156.4 $ 83.4 $ — $ 73.0 Standby letters of credit (b) 19.9 19.8 0.1 — Surety bonds (c) 33.2 33.2 — — Other guarantees (d) 67.0 4.3 0.1 62.6 Total $ 276.5 $ 140.7 $ 0.2 $ 135.6 (a) Consists of (a) $5.0 million and $6.0 million to support the business operations of WEC Business Services, LLC and WPS Power Development, LLC (PDL), respectively, and (b) $1.1 million , $109.3 million , and $35.0 million related to natural gas supply at Integrys Transportation Fuels, LLC (ITF), Minnesota Energy Resources Corporation (MERC), and MGU, respectively. These guarantees are not reflected on our balance sheets. (b) At our request or the request of our subsidiaries, financial institutions have issued standby letters of credit for the benefit of third parties that have extended credit to our subsidiaries. This amount consists of standby letters of credit issued to primarily support ITF, MERC, MGU, NSG, PDL, PGL, WPS, and Wisconsin Electric. This amount is not reflected on our balance sheets. (c) Primarily for the construction and operation of compressed natural gas fueling stations by ITF, workers compensation self-insurance programs, and obtaining various licenses, permits, and rights-of-way. These guarantees are not reflected on our balance sheets. (d) Consists of (a) $34.6 million to support PDL's future payment obligations related to its distributed solar generation projects; (b) $10.0 million related to the sale of a nonregulated retail marketing business previously owned by Integrys; (c) $11.2 million related to the performance of an operating and maintenance agreement by ITF; (d) $6.9 million related to other indemnifications primarily for workers compensation coverage; and (e) $3.7 million related to workers compensation obligations. The amounts discussed in items (a), (c), and (d) above are not reflected on our balance sheets. In addition, an insignificant liability was recorded for item (b) related to the possible imposition of additional miscellaneous gross receipts tax in the event of a change in law or interpretation of the law.

Benefits

Benefits	6 Months Ended
	Jun. 30, 2015
General Discussion of Pension and Other Postretirement Benefits [Abstract]
BENEFITS	BENEFITS The components of our net periodic pension and Other Post-Retirement Employee Benefits (OPEB) costs for the three and six months ended June 30 were as follows: Pension Costs Three Months Ended June 30 Six Months Ended June 30 Benefit Plan Cost Components 2015 2014 2015 2014 (Millions of Dollars) Net Periodic Benefit Cost Service cost $ 3.9 $ 2.3 $ 7.8 $ 5.0 Interest cost 15.1 17.0 30.3 34.1 Expected return on plan assets (25.6 ) (24.6 ) (51.4 ) (49.3 ) Amortization of: Prior service cost 0.5 0.5 1.0 1.0 Actuarial loss 11.4 9.3 23.0 18.4 Net Periodic Benefit Cost $ 5.3 $ 4.5 $ 10.7 $ 9.2 OPEB Costs Three Months Ended June 30 Six Months Ended June 30 Benefit Plan Cost Components 2015 2014 2015 2014 (Millions of Dollars) Net Periodic Benefit Cost Service cost $ 2.1 $ 2.1 $ 4.7 $ 4.3 Interest cost 3.9 4.4 8.1 8.9 Expected return on plan assets (5.9 ) (6.0 ) (11.8 ) (11.9 ) Amortization of: Transition obligation — — — — Prior service (credit) (0.3 ) (0.4 ) (0.6 ) (0.9 ) Actuarial loss 0.5 0.4 1.0 0.6 Net Periodic Benefit Cost $ 0.3 $ 0.5 $ 1.4 $ 1.0 We contributed $100.0 million to our qualified pension plan during the first six months of 2015 . No such contribution was made during the first six months of 2014 . Postemployment Benefits: Postemployment benefits provided to former or inactive employees are recognized when an event occurs. The estimated liability for such benefits was $7.0 million as of June 30, 2015 and $3.3 million as of December 31, 2014 .

Goodwill

Goodwill	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	GOODWILL The following table shows the carrying amount of goodwill for WEC Energy Group. In regard to the acquisition of Integrys, the allocation of goodwill to business segments has not yet been determined due to the short timeframe between the acquisition close date and the filing date of this report. (Millions of Dollars) Balance at December 31, 2014: $ 441.9 Acquisition (a) 2,944.6 Balance at June 30, 2015: $ 3,386.5 (a) Represents goodwill resulting from the acquisition of Integrys. See Note 2 -- Acquisition for additional information.

Investment in ATC

Investment in ATC	6 Months Ended
	Jun. 30, 2015
Equity Method Investments and Joint Ventures [Abstract]
INVESTMENT IN ATC	INVESTMENT IN ATC As a result of the acquisition, our ownership of ATC increased from 26.2% to approximately 60% as of June 30, 2015. ATC is a for-profit, transmission-only company regulated by FERC. The following table shows changes to our investment in ATC: Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars) (Millions of Dollars) Balance at beginning of period: $ 431.1 $ 409.6 $ 424.1 $ 402.7 Add: Earnings from equity method investment 14.3 17.5 30.4 34.8 Add: Capital contributions 1.2 3.9 2.5 7.8 Add: Acquisition of Integrys equity in ATC 552.0 — 552.0 — Less: Distributions received 10.8 14.2 21.2 28.5 Balance at end of period: $ 987.8 $ 416.8 $ 987.8 $ 416.8 Summarized financial data for ATC is included in the following tables: Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars) Income Statement Data Revenues $ 165.2 $ 160.0 $ 317.5 $ 323.3 Operating expenses 80.3 74.4 160.3 153.0 Other expense 24.3 21.9 48.6 43.5 Net Income $ 60.6 $ 63.7 $ 108.6 $ 126.8 June 30, 2015 December 31, 2014 (Millions of Dollars) Balance Sheet Data Current assets $ 78.1 $ 66.4 Noncurrent assets 3,835.2 3,728.7 Total assets $ 3,913.3 $ 3,795.1 Current liabilities $ 255.7 $ 313.1 Long-term debt 1,800.0 1,701.0 Other noncurrent liabilities 197.7 163.8 Shareholders' equity 1,659.9 1,617.2 Total liabilities and shareholders' equity $ 3,913.3 $ 3,795.1

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2015
Segment Information [Abstract]
SEGMENT INFORMATION	SEGMENT INFORMATION The acquisition of Integrys closed on June 29, 2015 , one day prior to the close of the period. The earnings during the three and six months ended June 30, 2015 exclude the operating results of Integrys. Acquisition-related costs are reflected in Corporate & Other. Our reporting segments will be evaluated for revision in the future. Summarized financial information concerning our reportable segments for the three and six months ended June 30, 2015 and 2014 is shown in the following table: Reportable Segments Eliminations Energy Corporate & & Reconciling Total Three Months Ended Utility Non-Utility Other (a) Items Consolidated (Millions of Dollars) June 30, 2015 Operating Revenues (b) $ 979.9 $ 115.3 $ 0.5 $ (104.5 ) $ 991.2 Other Operation and Maintenance $ 368.3 $ 4.7 $ 68.1 $ (104.1 ) $ 337.0 Depreciation and Amortization $ 88.5 $ 17.1 $ 0.1 $ — $ 105.7 Operating Income (Loss) $ 140.4 $ 93.5 $ (68.1 ) $ — $ 165.8 Equity in Earnings of Unconsolidated Affiliates $ 14.3 $ — $ (0.1 ) $ — $ 14.2 Interest Expense, Net $ 32.4 $ 15.9 $ 14.0 $ (0.2 ) $ 62.1 Income Tax Expense (Benefit) $ 44.0 $ 38.4 $ (19.2 ) $ — $ 63.2 Net Income (Loss) $ 82.1 $ 39.5 $ 82.1 $ (122.8 ) $ 80.9 Capital Expenditures $ 201.0 $ 3.2 $ 2.8 $ — $ 207.0 June 30, 2014 Operating Revenues (b) $ 1,029.8 $ 113.4 $ 0.3 $ (99.8 ) $ 1,043.7 Other Operation and Maintenance $ 343.6 $ 5.0 $ 6.1 $ (98.7 ) $ 256.0 Depreciation and Amortization $ 84.3 $ 16.7 $ 0.4 $ — $ 101.4 Operating Income (Loss) $ 155.2 $ 91.7 $ (6.2 ) $ — $ 240.7 Equity in Earnings of Unconsolidated Affiliates $ 17.5 $ — $ — $ — $ 17.5 Interest Expense, Net $ 30.7 $ 16.2 $ 12.2 $ (0.1 ) $ 59.0 Income Tax Expense (Benefit) $ 51.4 $ 30.2 $ (7.3 ) $ — $ 74.3 Net Income (Loss) $ 96.3 $ 45.4 $ 132.9 $ (141.6 ) $ 133.0 Capital Expenditures $ 172.6 $ 4.6 $ (0.9 ) $ — $ 176.3 Reportable Segments Eliminations Energy Corporate & & Reconciling Total Six Months Ended Utility Non-Utility Other (a) Items Consolidated (Millions of Dollars) June 30, 2015 Operating Revenues (b) $ 2,356.8 $ 225.0 $ 0.8 $ (203.5 ) $ 2,379.1 Other Operation and Maintenance $ 737.4 $ 5.8 $ 77.5 $ (203.0 ) $ 617.7 Depreciation and Amortization $ 176.4 $ 34.1 $ 0.3 $ — $ 210.8 Operating Income (Loss) $ 416.9 $ 185.1 $ (77.4 ) $ — $ 524.6 Equity in Earnings of Unconsolidated Affiliates $ 30.4 $ — $ (0.1 ) $ — $ 30.3 Interest Expense, Net $ 64.1 $ 31.8 $ 26.2 $ (0.3 ) $ 121.8 Income Tax Expense (Benefit) $ 141.8 $ 69.0 $ (25.2 ) $ — $ 185.6 Net Income (Loss) $ 247.2 $ 84.7 $ 279.1 $ (334.3 ) $ 276.7 Capital Expenditures $ 345.2 $ 7.2 $ 4.1 $ — $ 356.5 June 30, 2014 Operating Revenues (b) $ 2,711.9 $ 221.7 $ 0.6 $ (195.5 ) $ 2,738.7 Other Operation and Maintenance $ 711.2 $ 6.2 $ 7.3 $ (193.3 ) $ 531.4 Depreciation and Amortization $ 167.9 $ 33.6 $ 0.5 $ — $ 202.0 Operating Income (Loss) $ 447.9 $ 181.9 $ (7.3 ) $ — $ 622.5 Equity in Earnings of Unconsolidated Affiliates $ 34.8 $ — $ — $ — $ 34.8 Interest Expense, Net $ 64.7 $ 32.5 $ 24.4 $ (0.3 ) $ 121.3 Income Tax Expense (Benefit) $ 158.8 $ 60.2 $ (14.4 ) $ — $ 204.6 Net Income (Loss) $ 265.7 $ 89.5 $ 340.4 $ (355.0 ) $ 340.6 Capital Expenditures $ 293.3 $ 9.7 $ 2.5 $ — $ 305.5 (a) Corporate & Other includes all other non-utility activities, primarily non-utility real estate investment and development by Wispark LLC, as well as interest on corporate debt. (b) An elimination for intersegment revenues is included in Operating Revenues. This elimination is primarily between We Power and Wisconsin Electric.

Variable Interest Entities

Variable Interest Entities	6 Months Ended
	Jun. 30, 2015
Variable Interest Entities [Abstract]
VARIABLE INTEREST ENTITIES	VARIABLE INTEREST ENTITIES The primary beneficiary of a variable interest entity must consolidate the related assets and liabilities. Certain disclosures are required by sponsors, significant interest holders in variable interest entities and potential variable interest entities. We assess our relationships with potential variable interest entities such as our coal suppliers, natural gas suppliers, coal and gas transporters, and other counterparties in power purchase agreements and joint ventures. In making this assessment, we consider the potential that our contracts or other arrangements provide subordinated financial support, the potential for us to absorb losses or rights to residual returns of the entity, the ability to directly or indirectly make decisions about the entities' activities, and other factors. We have identified a purchased power agreement which represents a variable interest. This agreement is for 236 MW of firm capacity from a gas-fired cogeneration facility and we account for it as a capital lease. The agreement includes no minimum energy requirements over the remaining term of approximately 7 years . We have examined the risks of the entity including operations and maintenance, dispatch, financing, fuel costs and other factors, and have determined that we are not the primary beneficiary of the entity. We do not hold an equity or debt interest in the entity and there is no residual guarantee associated with the purchased power agreement. We have approximately $152.2 million of required payments over the remaining term of this agreement. We believe that the required lease payments under this contract will continue to be recoverable in rates. Total capacity and lease payments under contracts considered variable interests for the six months ended June 30, 2015 and 2014 were $26.8 million and $26.7 million , respectively. Our maximum exposure to loss is limited to the capacity payments under the contract.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Environmental Matters: We periodically review our exposure for environmental remediation costs as evidence becomes available indicating that our liability has changed. Given current information, including the following, we believe that future costs in excess of the amounts accrued and/or disclosed on all presently known and quantifiable environmental contingencies will not be material to our financial position or results of operations. We have a program of comprehensive environmental remediation planning for former manufactured gas plant sites and coal combustion product disposal sites. We perform ongoing assessments of manufactured gas plant sites and related disposal sites, as well as coal combustion product disposal/landfill sites used by our utilities. We are working with various state jurisdictions in our investigation and remediation planning. In addition, certain of our natural gas utilities are coordinating the investigation and cleanup of the sites subject to the jurisdiction of the United States Environmental Protection Agency (EPA) under what is called a "multisite" program. This program involves prioritizing the work to be done at the sites, preparation and approval of documents common to all of the sites, and use of a consistent approach in selecting remedies. At this time, we cannot estimate future remediation costs associated with these sites beyond those described below. Manufactured Gas Plant Sites: We have identified several sites at which our utilities or a predecessor company owned or operated a manufactured gas plant. These sites are at various stages of investigation, monitoring, and remediation. We have also identified other sites that may have been impacted by historical manufactured gas plant activities. Our natural gas utilities are responsible for the environmental remediation of these sites, some of which are in the EPA Superfund Program. The future costs for detailed site investigation and future remediation is dependent upon several variables including, among other things, the extent of remediation, changes in technology and changes in regulation. Historically, our regulators have allowed us to recover incurred costs, net of insurance recoveries, associated with the remediation of manufactured gas plant sites. Accordingly, we have established regulatory assets for costs associated with these sites. We have established the following reserves and regulatory assets related to manufactured gas plant sites: June 30, 2015 December 31, 2014 (Millions of Dollars) Regulatory Assets $ 670.7 $ 45.9 Reserves for Future Remediation $ 608.6 $ 32.6 The increase in the regulatory assets and reserves is primarily related to balances associated with the Integrys regulated companies. Illinois Investigations: In March 2015, the ICC opened a docket, naming PGL as respondent, to investigate the veracity of certain allegations included in anonymous letters that the ICC staff received. The allegations mainly focus on the management of the Accelerated Natural Gas Main Replacement Program (AMRP). The initiating order stated that the investigation would also include any further allegations of a similar nature as they pertain to AMRP. The Illinois Attorney General’s office is also conducting an investigation into the same matters. The investigations are ongoing. We plan to engage a nationally recognized firm to help conduct an independent, bottom up review of the cost, scope, and schedule for the program.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	6 Months Ended
	Jun. 30, 2015
Supplemental Cash Flow Information [Abstract]
SUPPLEMENTAL CASH FLOW INFORMATION	SUPPLEMENTAL CASH FLOW INFORMATION During the six months ended June 30, 2015 , we paid $116.9 million in interest, net of amounts capitalized, and paid $3.0 million in income taxes, net of refunds. During the six months ended June 30, 2014 , we paid $122.4 million in interest, net of amounts capitalized, and paid $17.6 million in income taxes, net of refunds. As of June 30, 2015 and 2014 , the amount of accounts payable related to capital expenditures was $3.5 million and $3.2 million , respectively. During the six months ended June 30, 2015 and 2014 , total amortization of deferred revenue was $20.7 million and $27.8 million , respectively.

Michigan Settlement (Notes)

Michigan Settlement (Notes)	6 Months Ended
	Jun. 30, 2015
Michigan Settlement [Abstract]
Michigan Settlement Disclosure [Text Block]	MICHIGAN SETTLEMENT In March 2015, we entered into an Amended and Restated Settlement Agreement (Amended Agreement) with the Attorney General of the State of Michigan, the Staff of the MPSC, and Tilden Mining Company and Empire Iron Mining Partnership to resolve all objections to our acquisition of Integrys these parties raised at the MPSC. The agreement includes the following provisions: • The parties to the Amended Agreement agree that the proposed acquisition satisfies the applicable requirements under Michigan law and should be approved by the MPSC. • Wisconsin Electric will not enter into a System Support Resource (SSR) agreement for the operation of Presque Isle Power Plant (PIPP) so long as both mines, if operational, remain full requirements customers of Wisconsin Electric until the earlier of (i) the date a new, clean generation plant located in the Upper Peninsula of Michigan commences commercial operation or (ii) December 31, 2019. (The prior SSR agreement was terminated effective February 1, 2015 with the return of the mines as full requirements customers.) • We commit to invest either through an ownership interest or a purchased power agreement, or to have, if formed, our future Michigan jurisdictional utility invest, in this plant subject to the issuance of a Certificate of Necessity from the MPSC. The costs of this plant would be recovered from Michigan customers. In addition, in March 2015, Wisconsin Electric entered into a special contract with each of the mines to provide full requirements electric service through December 31, 2019. In April 2015, the MPSC approved our acquisition of Integrys, the Amended Agreement and the special contracts with the two mines.

New Accounting Pronouncements

New Accounting Pronouncements	6 Months Ended
	Jun. 30, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Description of New Accounting Pronouncements Not yet Adopted [Text Block]	NEW ACCOUNTING PRONOUNCEMENTS Revenue Recognition: In May 2014, the Financial Accounting Standards Board (FASB) and the International Accounting Standards Board issued their joint revenue recognition standard, Accounting Standards Update 2014-09, Revenue from Contracts with Customers. The guidance is based on the principle that revenue is recognized when promised goods or services are transferred to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. This guidance is effective for fiscal years and interim periods beginning after December 15, 2017, with early adoption for fiscal years and interim periods beginning after December 15, 2016 permitted. The standard can either be applied retrospectively or as a cumulative-effect adjustment as of the date of adoption. We are currently assessing the effects this guidance may have on our consolidated financial statements. Debt Issuance Costs: In April 2015, the FASB issued Accounting Standards Update 2015-03, Simplifying the Presentation of Debt Issuance Costs. The guidance requires debt issuance costs to be presented on the balance sheet as a reduction to the carrying value of the corresponding debt, rather than as an asset as it is currently presented. This guidance is effective for fiscal years and interim periods beginning after December 15, 2015. The standard requires retrospective application by restating each prior period presented in the financial statements. We are currently assessing the effects this guidance may have on our consolidated financial statements.

Acquisition (Tables)

Acquisition (Tables)	6 Months Ended
	Jun. 30, 2015
Business Combinations [Abstract]
Schedule of Business Acquisitions by Acquisition, Equity Interest Issued or Issuable [Table Text Block]	The total consideration transferred was based on the closing price of Wisconsin Energy common stock on June 29, 2015 , and was calculated as follows: Stock Cash Total (Millions of Dollars, except per share amounts) Integrys common shares outstanding at June 29, 2015 79,963,091 79,963,091 Exchange ratio 1.128 Wisconsin Energy shares issued for Integrys shares (a) 90,187,884 Closing price of Wisconsin Energy common shares on June 29, 2015 $45.16 Fair value of common stock issued $ 4,072.9 $ 4,072.9 Cash paid per share of Integrys shares outstanding $18.58 Fair value of cash paid for Integrys shares (a) $ 1,486.2 $ 1,486.2 Consideration attributable to settlement of equity awards, net of tax $ 24.0 $ 24.0 Total purchase price $ 4,072.9 $ 1,510.2 $ 5,583.1 (a) 10,483 fractional shares totaling $0.5 million were paid in cash.
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	The preliminary purchase price allocation of the acquisition was as follows: (Millions of Dollars) Current assets $ 1,178.2 Net property, plant and equipment 7,098.2 Goodwill 2,944.6 Deferred charges and other assets, excluding goodwill 2,410.5 Current liabilities, including current maturities of long-term debt (1,260.1 ) Deferred credits and other liabilities (3,769.6 ) Long-term debt (2,967.6 ) Preferred stock of subsidiary (51.1 ) Total purchase price $ 5,583.1
Business Acquisition, Pro Forma Information [Table Text Block]	Unaudited Pro Forma Financial Information Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars, Except Per Share Amounts) Operating Revenues $ 1,629.2 $ 1,879.5 $ 4,180.1 $ 5,208.2 Net Income $ 159.1 $ 143.2 $ 488.7 $ 499.5 Earnings per share (Basic) $ 0.50 $ 0.46 $ 1.55 $ 1.54 Earnings per share (Diluted) $ 0.50 $ 0.45 $ 1.54 $ 1.53

Common Equity (Tables)

Common Equity (Tables)	6 Months Ended
	Jun. 30, 2015
Common Equity (Tables) [Abstract]
Shares Repurchased [Table Text Block]	Six Months Ended June 30 2015 2014 Shares Cost Shares Cost (In Millions) Under share repurchase program — $ — 0.4 $ 18.6 To fulfill exercised stock options and restricted stock awards 0.6 32.0 0.9 38.7 Total 0.6 $ 32.0 1.3 $ 57.3
Assumptions for valuing options using binomial option pricing model	2015 2014 Non-qualified stock options granted year to date 516,475 899,500 Estimated fair value per non-qualified stock option $ 5.29 $ 4.18 Assumptions used to value the options using a binomial option pricing model: Risk-free interest rate 0.1% - 2.1% 0.1% - 3.0% Dividend yield 3.7 % 3.8 % Expected volatility 18.0 % 18.0 % Expected forfeiture rate 2.0 % 2.0 % Expected life (years) 5.8 5.8
Stock option activity	Weighted- Average Weighted- Remaining Aggregate Number of Average Contractual Life Intrinsic Value Stock Options Options Exercise Price (Years) (Millions) Outstanding as of April 1, 2015 6,927,549 $ 32.04 Granted — $ — Exercised (176,619 ) $ 21.10 Forfeited — $ — Outstanding as of June 30, 2015 6,750,930 $ 32.32 Outstanding as of January 1, 2015 6,770,194 $ 29.99 Granted 516,475 $ 52.90 Exercised (535,739 ) $ 22.73 Forfeited — $ — Outstanding as of June 30, 2015 6,750,930 $ 32.32 5.7 $ 85.4 Exercisable as of June 30, 2015 4,014,465 $ 26.06 4.0 $ 75.9
Non-vested options	Weighted-Average Non-Vested Stock Options Number of Options Fair Value Non-vested as of April 1, 2015 2,736,465 $ 4.03 Granted — $ — Vested — $ — Forfeited — $ — Non-vested as of June 30, 2015 2,736,465 $ 4.03 Non-vested as of January 1, 2015 2,879,855 $ 3.65 Granted 516,475 $ 5.29 Vested (659,865 ) $ 3.34 Forfeited — $ — Non-vested as of June 30, 2015 2,736,465 $ 4.03
Restricted stock activity	Weighted-Average Restricted Shares Number of Shares Grant Date Fair Value Outstanding as of April 1, 2015 147,214 Granted — $ — Released — $ — Forfeited — $ — Outstanding as of June 30, 2015 147,214 Outstanding as of January 1, 2015 155,479 Granted 60,164 $ 53.83 Released (68,429 ) $ 36.95 Forfeited — $ — Outstanding as of June 30, 2015 147,214
Dividends Declared [Table Text Block]	During the quarter ended June 30, 2015, our Board of Directors declared common stock dividends which are summarized below: Date Declared Date Payable Per Share Period April 16, 2015 June 1, 2015 $0.4225 Second Quarter June 12, 2015 July 6, 2015 $0.2067 45 days through June 28, 2015 June 12, 2015 September 1, 2015 $0.2337 47 days through Aug. 14, 2015

Materials, Supplies and Inven26

Materials, Supplies and Inventories (Tables)	6 Months Ended
	Jun. 30, 2015
Inventory Disclosure [Abstract]
Schedule of Inventory, Current [Table Text Block]	Our inventory consists of: Materials, Supplies and Inventories June 30, 2015 December 31, 2014 (Millions of Dollars) Fossil Fuel $ 182.4 $ 125.6 Materials and Supplies 249.7 150.2 Natural Gas in Storage 130.4 124.8 Total $ 562.5 $ 400.6
Schedule of LIFO liquidation balance sheet amount	The amounts as of June 30, 2015 were as follows: As of June 30, 2015 Balance Sheet Presentation PGL NSG (Millions of Dollars) Temporary LIFO liquidation debit Other current assets $ 21.0 $ — Temporary LIFO liquidation credit Other current Liabilities $ — $ 5.2

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Measurements (Tables) [Abstract]
Financial assets and liabilities by level within the fair value hierarchy	Recurring Fair Value Measures As of June 30, 2015 Level 1 Level 2 Level 3 Total (Millions of Dollars) Assets: Derivatives $ 3.5 $ 4.1 $ 7.7 $ 15.3 Total $ 3.5 $ 4.1 $ 7.7 $ 15.3 Liabilities: Derivatives $ 6.7 $ 26.6 $ 5.4 $ 38.7 Total $ 6.7 $ 26.6 $ 5.4 $ 38.7 Recurring Fair Value Measures As of December 31, 2014 Level 1 Level 2 Level 3 Total (Millions of Dollars) Assets: Derivatives $ 1.1 $ 7.2 $ 7.0 $ 15.3 Total $ 1.1 $ 7.2 $ 7.0 $ 15.3 Liabilities: Derivatives $ 11.5 $ 1.0 $ — $ 12.5 Total $ 11.5 $ 1.0 $ — $ 12.5
Fair value of derivatives classified as Level 3 in the fair value hierarchy	Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars) Beginning Balance $ 3.3 $ 1.7 $ 7.0 $ 3.5 Realized and unrealized gains (losses) — — — — Purchases 3.9 15.6 3.9 15.6 Issuances — — — — Settlements (3.6 ) (3.2 ) (7.3 ) (5.0 ) Acquisition of Integrys (1.3 ) — (1.3 ) — Transfers in and/or out of Level 3 — — — — Balance as of June 30 $ 2.3 $ 14.1 $ 2.3 $ 14.1
Carrying amount and estimated fair value of certain financial instruments	June 30, 2015 December 31, 2014 Financial Instruments Carrying Amount Fair Value Carrying Amount Fair Value (Millions of Dollars) Preferred stock, no redemption required $ 81.5 $ 80.1 $ 30.4 $ 27.1 Long-term debt, including current portion $ 9,118.4 $ 9,181.1 $ 4,552.4 $ 5,126.0

Derivative Instruments (Tables)

Derivative Instruments (Tables)	6 Months Ended
	Jun. 30, 2015
Derivative Instruments (Tables) [Abstract]
Derivative instruments in balance sheet	June 30, 2015 December 31, 2014 Derivative Asset Derivative Liability Derivative Asset Derivative Liability (Millions of Dollars) Natural Gas $ 6.2 $ 26.9 $ 5.0 $ 12.3 Fuel Oil 0.1 0.9 — — FTRs 7.7 — 7.0 — Coal 1.3 10.9 3.3 0.2 Total $ 15.3 $ 38.7 $ 15.3 $ 12.5
Derivative instruments' estimated notional volumes and gain (losses)	Three Months Ended June 30, 2015 Three Months Ended June 30, 2014 Volume Gains (Losses) Volume Gains (Losses) (Millions of Dollars) (Millions of Dollars) Natural Gas 10.0 million Dth $ (5.9 ) 9.9 million Dth $ 2.5 Fuel Oil 0.8 million gallons 0.1 2.4 million gallons 0.4 FTRs 5.9 million MWh 0.8 7.4 million MWh 2.6 Total $ (5.0 ) $ 5.5 Six Months Ended June 30, 2015 Six Months Ended June 30, 2014 Volume Gains (Losses) Volume Gains (Losses) (Millions of Dollars) (Millions of Dollars) Natural Gas 23.3 million Dth $ (13.0 ) 24.8 million Dth $ 10.1 Fuel Oil 1.7 million gallons — 4.4 million gallons 0.6 FTRs 12.1 million MWh 2.9 13.1 million MWh 9.6 Total $ (10.1 ) $ 20.3
Offsetting Assets and Liabilities [Table Text Block]	June 30, 2015 December 31, 2014 Derivative Derivative Derivative Derivative Asset Liability Asset Liability (Millions of Dollars) Gross Amount Recognized on the Balance Sheet $ 15.3 $ 38.7 $ 15.3 $ 12.5 Gross Amount Not Offset on Balance Sheet (a) (4.9 ) (8.9 ) (0.4 ) (11.5 ) Net Amount $ 10.4 $ 29.8 $ 14.9 $ 1.0 (a) Gross Amount Not Offset on Balance Sheet includes cash collateral posted of $3.9 million and $10.3 million as of June 30, 2015 and December 31, 2014 , respectively.

Guarantees (Tables)

Guarantees (Tables)	6 Months Ended
	Jun. 30, 2015
Guarantees [Abstract]
Schedule of outstanding guarantees	The following table shows our outstanding guarantees: Total Amounts Expiration Committed at Less Than 1 to 3 Over 3 June 30, 2015 1 Year Years Years (Millions of Dollars) Guarantees: Guarantees supporting commodity transactions of subsidiaries (a) $ 156.4 $ 83.4 $ — $ 73.0 Standby letters of credit (b) 19.9 19.8 0.1 — Surety bonds (c) 33.2 33.2 — — Other guarantees (d) 67.0 4.3 0.1 62.6 Total $ 276.5 $ 140.7 $ 0.2 $ 135.6 (a) Consists of (a) $5.0 million and $6.0 million to support the business operations of WEC Business Services, LLC and WPS Power Development, LLC (PDL), respectively, and (b) $1.1 million , $109.3 million , and $35.0 million related to natural gas supply at Integrys Transportation Fuels, LLC (ITF), Minnesota Energy Resources Corporation (MERC), and MGU, respectively. These guarantees are not reflected on our balance sheets. (b) At our request or the request of our subsidiaries, financial institutions have issued standby letters of credit for the benefit of third parties that have extended credit to our subsidiaries. This amount consists of standby letters of credit issued to primarily support ITF, MERC, MGU, NSG, PDL, PGL, WPS, and Wisconsin Electric. This amount is not reflected on our balance sheets. (c) Primarily for the construction and operation of compressed natural gas fueling stations by ITF, workers compensation self-insurance programs, and obtaining various licenses, permits, and rights-of-way. These guarantees are not reflected on our balance sheets. (d) Consists of (a) $34.6 million to support PDL's future payment obligations related to its distributed solar generation projects; (b) $10.0 million related to the sale of a nonregulated retail marketing business previously owned by Integrys; (c) $11.2 million related to the performance of an operating and maintenance agreement by ITF; (d) $6.9 million related to other indemnifications primarily for workers compensation coverage; and (e) $3.7 million related to workers compensation obligations. The amounts discussed in items (a), (c), and (d) above are not reflected on our balance sheets. In addition, an insignificant liability was recorded for item (b) related to the possible imposition of additional miscellaneous gross receipts tax in the event of a change in law or interpretation of the law.

Benefits (Tables)

Benefits (Tables)	6 Months Ended
	Jun. 30, 2015
Benefits (Tables) [Abstract]
Components of net periodic pension and OPEB costs	Pension Costs Three Months Ended June 30 Six Months Ended June 30 Benefit Plan Cost Components 2015 2014 2015 2014 (Millions of Dollars) Net Periodic Benefit Cost Service cost $ 3.9 $ 2.3 $ 7.8 $ 5.0 Interest cost 15.1 17.0 30.3 34.1 Expected return on plan assets (25.6 ) (24.6 ) (51.4 ) (49.3 ) Amortization of: Prior service cost 0.5 0.5 1.0 1.0 Actuarial loss 11.4 9.3 23.0 18.4 Net Periodic Benefit Cost $ 5.3 $ 4.5 $ 10.7 $ 9.2 OPEB Costs Three Months Ended June 30 Six Months Ended June 30 Benefit Plan Cost Components 2015 2014 2015 2014 (Millions of Dollars) Net Periodic Benefit Cost Service cost $ 2.1 $ 2.1 $ 4.7 $ 4.3 Interest cost 3.9 4.4 8.1 8.9 Expected return on plan assets (5.9 ) (6.0 ) (11.8 ) (11.9 ) Amortization of: Transition obligation — — — — Prior service (credit) (0.3 ) (0.4 ) (0.6 ) (0.9 ) Actuarial loss 0.5 0.4 1.0 0.6 Net Periodic Benefit Cost $ 0.3 $ 0.5 $ 1.4 $ 1.0

Goodwill (Tables)

Goodwill (Tables)	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table shows the carrying amount of goodwill for WEC Energy Group. In regard to the acquisition of Integrys, the allocation of goodwill to business segments has not yet been determined due to the short timeframe between the acquisition close date and the filing date of this report. (Millions of Dollars) Balance at December 31, 2014: $ 441.9 Acquisition (a) 2,944.6 Balance at June 30, 2015: $ 3,386.5 (a) Represents goodwill resulting from the acquisition of Integrys. See Note 2 -- Acquisition for additional information.

Investment in ATC (Tables)

Investment in ATC (Tables) - ATC	6 Months Ended
	Jun. 30, 2015
Investment in ATC
Schedule of changes to our investment in ATC	The following table shows changes to our investment in ATC: Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars) (Millions of Dollars) Balance at beginning of period: $ 431.1 $ 409.6 $ 424.1 $ 402.7 Add: Earnings from equity method investment 14.3 17.5 30.4 34.8 Add: Capital contributions 1.2 3.9 2.5 7.8 Add: Acquisition of Integrys equity in ATC 552.0 — 552.0 — Less: Distributions received 10.8 14.2 21.2 28.5 Balance at end of period: $ 987.8 $ 416.8 $ 987.8 $ 416.8
Schedule of summarized income statement data for ATC	Summarized financial data for ATC is included in the following tables: Three Months Ended June 30 Six Months Ended June 30 2015 2014 2015 2014 (Millions of Dollars) Income Statement Data Revenues $ 165.2 $ 160.0 $ 317.5 $ 323.3 Operating expenses 80.3 74.4 160.3 153.0 Other expense 24.3 21.9 48.6 43.5 Net Income $ 60.6 $ 63.7 $ 108.6 $ 126.8
Schedule of summarized balance sheet data for ATC	June 30, 2015 December 31, 2014 (Millions of Dollars) Balance Sheet Data Current assets $ 78.1 $ 66.4 Noncurrent assets 3,835.2 3,728.7 Total assets $ 3,913.3 $ 3,795.1 Current liabilities $ 255.7 $ 313.1 Long-term debt 1,800.0 1,701.0 Other noncurrent liabilities 197.7 163.8 Shareholders' equity 1,659.9 1,617.2 Total liabilities and shareholders' equity $ 3,913.3 $ 3,795.1

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2015
Segment Information [Abstract]
Financial information of reportable operating segments	Reportable Segments Eliminations Energy Corporate & & Reconciling Total Three Months Ended Utility Non-Utility Other (a) Items Consolidated (Millions of Dollars) June 30, 2015 Operating Revenues (b) $ 979.9 $ 115.3 $ 0.5 $ (104.5 ) $ 991.2 Other Operation and Maintenance $ 368.3 $ 4.7 $ 68.1 $ (104.1 ) $ 337.0 Depreciation and Amortization $ 88.5 $ 17.1 $ 0.1 $ — $ 105.7 Operating Income (Loss) $ 140.4 $ 93.5 $ (68.1 ) $ — $ 165.8 Equity in Earnings of Unconsolidated Affiliates $ 14.3 $ — $ (0.1 ) $ — $ 14.2 Interest Expense, Net $ 32.4 $ 15.9 $ 14.0 $ (0.2 ) $ 62.1 Income Tax Expense (Benefit) $ 44.0 $ 38.4 $ (19.2 ) $ — $ 63.2 Net Income (Loss) $ 82.1 $ 39.5 $ 82.1 $ (122.8 ) $ 80.9 Capital Expenditures $ 201.0 $ 3.2 $ 2.8 $ — $ 207.0 June 30, 2014 Operating Revenues (b) $ 1,029.8 $ 113.4 $ 0.3 $ (99.8 ) $ 1,043.7 Other Operation and Maintenance $ 343.6 $ 5.0 $ 6.1 $ (98.7 ) $ 256.0 Depreciation and Amortization $ 84.3 $ 16.7 $ 0.4 $ — $ 101.4 Operating Income (Loss) $ 155.2 $ 91.7 $ (6.2 ) $ — $ 240.7 Equity in Earnings of Unconsolidated Affiliates $ 17.5 $ — $ — $ — $ 17.5 Interest Expense, Net $ 30.7 $ 16.2 $ 12.2 $ (0.1 ) $ 59.0 Income Tax Expense (Benefit) $ 51.4 $ 30.2 $ (7.3 ) $ — $ 74.3 Net Income (Loss) $ 96.3 $ 45.4 $ 132.9 $ (141.6 ) $ 133.0 Capital Expenditures $ 172.6 $ 4.6 $ (0.9 ) $ — $ 176.3 Reportable Segments Eliminations Energy Corporate & & Reconciling Total Six Months Ended Utility Non-Utility Other (a) Items Consolidated (Millions of Dollars) June 30, 2015 Operating Revenues (b) $ 2,356.8 $ 225.0 $ 0.8 $ (203.5 ) $ 2,379.1 Other Operation and Maintenance $ 737.4 $ 5.8 $ 77.5 $ (203.0 ) $ 617.7 Depreciation and Amortization $ 176.4 $ 34.1 $ 0.3 $ — $ 210.8 Operating Income (Loss) $ 416.9 $ 185.1 $ (77.4 ) $ — $ 524.6 Equity in Earnings of Unconsolidated Affiliates $ 30.4 $ — $ (0.1 ) $ — $ 30.3 Interest Expense, Net $ 64.1 $ 31.8 $ 26.2 $ (0.3 ) $ 121.8 Income Tax Expense (Benefit) $ 141.8 $ 69.0 $ (25.2 ) $ — $ 185.6 Net Income (Loss) $ 247.2 $ 84.7 $ 279.1 $ (334.3 ) $ 276.7 Capital Expenditures $ 345.2 $ 7.2 $ 4.1 $ — $ 356.5 June 30, 2014 Operating Revenues (b) $ 2,711.9 $ 221.7 $ 0.6 $ (195.5 ) $ 2,738.7 Other Operation and Maintenance $ 711.2 $ 6.2 $ 7.3 $ (193.3 ) $ 531.4 Depreciation and Amortization $ 167.9 $ 33.6 $ 0.5 $ — $ 202.0 Operating Income (Loss) $ 447.9 $ 181.9 $ (7.3 ) $ — $ 622.5 Equity in Earnings of Unconsolidated Affiliates $ 34.8 $ — $ — $ — $ 34.8 Interest Expense, Net $ 64.7 $ 32.5 $ 24.4 $ (0.3 ) $ 121.3 Income Tax Expense (Benefit) $ 158.8 $ 60.2 $ (14.4 ) $ — $ 204.6 Net Income (Loss) $ 265.7 $ 89.5 $ 340.4 $ (355.0 ) $ 340.6 Capital Expenditures $ 293.3 $ 9.7 $ 2.5 $ — $ 305.5 (a) Corporate & Other includes all other non-utility activities, primarily non-utility real estate investment and development by Wispark LLC, as well as interest on corporate debt. (b) An elimination for intersegment revenues is included in Operating Revenues. This elimination is primarily between We Power and Wisconsin Electric.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2015
Loss Contingencies [Line Items]
Schedule of Regulatory Assets and Reserves for Manufactured Gas Plant Sites	We have established the following reserves and regulatory assets related to manufactured gas plant sites: June 30, 2015 December 31, 2014 (Millions of Dollars) Regulatory Assets $ 670.7 $ 45.9 Reserves for Future Remediation $ 608.6 $ 32.6

Acquisition Consideration Trans

Acquisition Consideration Transferred (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended
	Jun. 30, 2015	Jun. 29, 2015
Acquisition
Percentage of Integrys common shares acquired		100.00%
WEC interest in ATC	60.00%	60.00%
Exchange ratio	1.128
Wisconsin Energy Shares issued for Integrys shares	90,187,884
Number of Wisconsin Energy fractional shares that were paid in cash		10,483
Dollar value of Wisconsin Energy fractional shares paid in cash		$ 0.5
Closing price of Wisconsin Energy common shares on June 29, 2015		$ 45.16
Fair value of common stock issued		$ 4,072.9
Cash paid per share of Integrys shares outstanding	$ 18.58
Fair value of cash paid for integrys shares		1,486.2
Consideration attributable to settlement of equity awards, net of tax		24
Total cash consideration paid for acquisition		$ 1,510.2
Total purchase price	$ 5,583.1
Integrys
Acquisition
WEC interest in ATC		34.00%
Integrys common shares outstanding at June 29, 2015		79,963,091

Acquisition Purchase Price Allo

Acquisition Purchase Price Allocation (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Jun. 29, 2015
Assets acquired
Current assets			$ 1,178.2
Property, plant and equipment			7,098.2
Goodwill	$ 2,944.6	$ 2,944.6
Other long-term assets, excluding Goodwill			2,410.5
Liabilities assumed
Current liabilities, including current maturities of long-term debt			(1,260.1)
Deferred credits and other liabilities			(3,769.6)
Long-term debt			(2,967.6)
Preferred stock of subsidiary			$ (51.1)
Acquisition purchase price	$ 5,583.1

Acquisition Approval Conditions

Acquisition Approval Conditions (Details)	1 Months Ended
	Jun. 30, 2015	Jun. 29, 2015
Acquisition
WEC interest in ATC	60.00%	60.00%
Wisconsin electric [Member]
Acquisition
Duration of earnings cap condition imposed by the PSCW	3 years
Wisconsin Gas [Member]
Acquisition
Duration of earnings cap condition imposed by the PSCW	3 years
PGL
Acquisition
Duration of rate base freeze condition imposed by the ICC	2 years
NSG
Acquisition
Duration of rate base freeze condition imposed by the ICC	2 years

Acquisition Pro Forma Financial

Acquisition Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Business Combinations [Abstract]
After-tax acquisition costs	$ 53.9	$ 3	$ 62.3	$ 3
After-tax acquisition costs (per share)	$ 0.24	$ 0.01	$ 0.28	$ 0.01
Operating Revenues	$ 1,629.2	$ 1,879.5	$ 4,180.1	$ 5,208.2
Net Income	$ 159.1	$ 143.2	$ 488.7	$ 499.5
Earnings per share (Basic)	$ 0.50	$ 0.46	$ 1.55	$ 1.54
Earnings per share (Diluted)	$ 0.50	$ 0.45	$ 1.54	$ 1.53

Common Equity (Details)

Common Equity (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Common Equity (Textuals) [Abstract]
Comprehensive Income, Net of Tax, Attributable to Parent	$ 92,200,000	$ 133,000,000	$ 288,000,000	$ 340,600,000
Other Comprehensive Income (Loss), Net of Tax	11,300,000	$ 0	$ 11,300,000	$ 0
Performance units [Member]
Common Equity (Textuals) [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			195,365	233,735
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value			$ 13,200,000	$ 14,800,000
Tax Benefit from Stock Options Exercised			4,800,000	5,300,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 14,200,000		$ 14,200,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition			23 months
Restricted stock [Member]
Common Equity (Textuals) [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0		60,164
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value			$ 3,700,000	2,700,000
Tax Benefit from Stock Options Exercised			1,300,000	$ 1,000,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 4,600,000		$ 4,600,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition			24 months

Common Equity Common Equity 1 (

Common Equity Common Equity 1 (Details) - $ / shares	3 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate		3.70%	3.80%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate		18.00%	18.00%
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Forfeiture Rate		2.00%	2.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term		5 years 10 months	5 years 10 months
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Net of Forfeitures	0	516,475	899,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value		$ 5.29	$ 4.18
Share Based Compensation Arrangement By Share Based Payment Award Options Grant In Period Weighted Average Exercise Price	$ 0	$ 52.90
Lower Range [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate		0.10%	0.10%
Upper Range [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate		2.10%	3.00%

Common Equity Common Equity 2 (

Common Equity Common Equity 2 (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	6,750,930		6,750,930
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 32.32		$ 32.32
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	4,014,465		4,014,465
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 26.06		$ 26.06
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value	$ 4.8	$ 2.2	$ 15.4	$ 17.5
Exercise of stock options			12.2	17.6
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options			$ 6.2	$ 7
Stock options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	6,927,549		6,770,194
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period	0		516,475	899,500
Share Based Compensation Arrangement By Share Based Payment Award Options Grant In Period Weighted Average Exercise Price	$ 0		$ 52.90
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(176,619)		(535,739)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	0		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	6,750,930		6,750,930
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 32.04		$ 29.99
Share Based Compensation Arrangement By Share Based Payment Awards Options Exercises In Period Weighted Average Exercise Price	21.10		22.73
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	0		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 32.32		$ 32.32
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range Outstanding Options Weighted Average Remaining Contractual Period			5 years 8 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 85.4		$ 85.4
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	4,014,465		4,014,465
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 26.06		$ 26.06
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term			4 years
Share Based Compensation Arrangement by Share Based Payments Award, Options Exercisable, Intrinsic Value	$ 75.9		$ 75.9

Common Equity Common Equity 3 (

Common Equity Common Equity 3 (Details) - Jun. 30, 2015 - $ / shares	Total
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	6,750,930
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 32.32
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	5 years 8 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	4,014,465
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 26.06
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	4 years
Exercise Price, Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	1,236,412
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 20.98
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 years 2 months
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	1,236,412
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 20.98
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	3 years 2 months
Exercise Price, Range One [Member] | Maximum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 21.11
Exercise Price, Range One [Member] | Minimum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 19.74
Exercise Price, Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	1,897,488
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 25.15
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 years 3 months
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	1,897,488
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 25.15
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	3 years 3 months
Exercise Price, Range Two [Member] | Maximum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 29.35
Exercise Price, Range Two [Member] | Minimum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 23.88
Exercise Price, Range Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	3,617,030
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 39.96
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	7 years 9 months
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	880,565
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 35.15
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Remaining Contractual Term	6 years 7 months
Exercise Price, Range Three [Member] | Maximum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 52.90
Exercise Price, Range Three [Member] | Minimum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 34.88

Common Equity Common Equity 4 (

Common Equity Common Equity 4 (Details) - Jun. 30, 2015 - USD ($) $ / shares in Units, $ in Millions	Total	Total
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	6,750,930	6,750,930
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 32.32	$ 32.32
Performance units [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition		23 months
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 14.2	$ 14.2
Non Vested Options [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	2,736,465	2,879,855
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period	0	516,475
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period	0	(659,865)
Share Based Compensation Arrangements By Share Based Payment Awards Options Vested In Period Weighted Average Fair Value Per Share	$ 0	$ 3.34
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	2,736,465	2,736,465
Non-vested options outstanding beginning balance, weighted average fair value	$ 4.03	$ 3.65
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	0	5.29
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Intrinsic Value	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 4.03	$ 4.03
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition		18 months
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 3.2	$ 3.2

Common Equity Common Equity 5 (

Common Equity Common Equity 5 (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other Comprehensive Income (Loss), Net of Tax	$ 11,300,000	$ 0	$ 11,300,000	$ 0
Stock Repurchased During Period, Shares			600,000	1,300,000
Stock Repurchased During Period, Value			$ 32,000,000	$ 57,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			3 years
Share Based Compensation Arrangement By Share Based Payment Award Award Percentage To Vest Each Year After Grant Date			33.00%
Share Repurchase Plan, 2013 [Member] [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Repurchase Program, Authorized Amount	$ 300,000,000		$ 300,000,000
Stock Repurchased During Period, Shares			0
Stock Repurchased During Period, Value			$ 0
Share Repurchase Plan, 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Repurchased During Period, Shares				400,000
Stock Repurchased During Period, Value				$ 18,600,000
Restricted stock [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, Vested in Period, Total Fair Value			$ 3,700,000	2,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	147,214		155,479
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0		60,164
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0		(68,429)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0		0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	147,214		147,214
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0		$ 53.83
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	0		36.95
Share Based Compensation Arrangement By Share Based Payment Awards Equity Instruments Other Than Options Forfeited In Period Weighted Average Grant Date Fair Value	$ 0		$ 0
Tax Benefit from Stock Options Exercised			$ 1,300,000	$ 1,000,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 4,600,000		$ 4,600,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition			24 months
Share Repurchases to Fulfill Exercised Stock Options and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Repurchased During Period, Shares			600,000	900,000
Stock Repurchased During Period, Value			$ 32,000,000	$ 38,700,000

Common Equity Common Equity 6 (

Common Equity Common Equity 6 (Details)	6 Months Ended
	Jun. 30, 2015
Dividend Payment Restrictions [Line Items]
Maximum debt to capitalization ratio required to be maintained (as a percent)	65.00%
PGL
Dividend Payment Restrictions [Line Items]
Maximum debt to capitalization ratio required to be maintained (as a percent)	65.00%
WPS [Member]
Dividend Payment Restrictions [Line Items]
Maximum debt to capitalization ratio required to be maintained (as a percent)	65.00%
WPS [Member] | Maximum [Member] | Public Service Commission of Wisconsin [Member]
Dividend Payment Restrictions [Line Items]
Percentage of previous period's dividend as restriction on current period dividends	103.00%
WPS [Member] | Minimum [Member]
Dividend Payment Restrictions [Line Items]
Percentage of common stockholders' equity to total capitalization required to be maintained	25.00%
WPS [Member] | Minimum [Member] | Public Service Commission of Wisconsin [Member]
Dividend Payment Restrictions [Line Items]
Common equity ratio required to be maintained (as a percent)	51.00%

Common Equity Common Equity 7 (

Common Equity Common Equity 7 (Details)	1 Months Ended
	Jun. 30, 2015shares
Common Equity 7 [Abstract]
Business Acquisition Equity Interest Issued or Issuable, Number of Shares	90,200,000
Wisconsin Energy Shares issued for Integrys shares	90,187,884

Common Equity Common Equity 8 (

Common Equity Common Equity 8 (Details) - $ / shares	Sep. 01, 2015	Jul. 06, 2015	Jun. 12, 2015	Apr. 16, 2015	Sep. 30, 2015	Jun. 30, 2015
Dividends Paid and Payable [Line Items]
Dividends Payable, Date Declared			Jun. 12, 2015			Apr. 16, 2015
Dividends Payable, Date to be Paid	Sep. 1, 2015	Jul. 6, 2015				Jun. 1, 2015
Common Stock, Dividends, Per Share, Declared		$ 0			$ 0.4575	$ 0.8629
Dividend Increase Percentage		8.30%
Dividends declared April 16, 2015, payable June 1, 2015 [Member]
Dividends Paid and Payable [Line Items]
Common Stock, Dividends, Per Share, Declared				$ 0.4225
Dividends declared June 12, 2015, payable July 6, 2015 [Member]
Dividends Paid and Payable [Line Items]
Common Stock, Dividends, Per Share, Declared			$ 0.2067
Dividends declared June 12, 2015, payable September 1, 2015 [Member]
Dividends Paid and Payable [Line Items]
Common Stock, Dividends, Per Share, Declared			$ 0.2337

Long Term Debt (Details)

Long Term Debt (Details) - USD ($) $ in Millions	1 Months Ended
	Jul. 31, 2015	Jun. 30, 2015	Apr. 30, 2014	May. 31, 2015	May. 31, 2014
Long Term Debt (Textuals)
Long-term Debt Assumed in Business Combination		$ 3,100
Fair Value Adjustment to Long-term Debt		45.7
WEC Senior Notes due June 15, 2018 [Member]
Long Term Debt (Textuals)
Issuance of long-term debt		$ 300
Interest rate on long-term debt		1.65%
WEC Senior Notes due June 15, 2020 [Member]
Long Term Debt (Textuals)
Issuance of long-term debt		$ 400
Interest rate on long-term debt		2.45%
WEC Senior Notes due June 15, 2025 [Member]
Long Term Debt (Textuals)
Issuance of long-term debt		$ 500
Interest rate on long-term debt		3.55%
Wis Elec Debenture due June 1, 2025 [Member]
Long Term Debt (Textuals)
Issuance of long-term debt				$ 250
Interest rate on long-term debt				3.10%
Wis Elec Debenture due June 1, 2044 [Member]
Long Term Debt (Textuals)
Issuance of long-term debt					$ 250
Interest rate on long-term debt					4.25%
Wis Elec Debentures due April 1, 2014 [Member]
Long Term Debt (Textuals)
Retirement of long-term debt			$ 300
Subsequent Event [Member] | TEG Senior Notes due June 1, 2016 [Member]
Long Term Debt (Textuals)
Offer to buy back $55 million 8% Senior Note	$ 55

Materials, Supplies and Inven49

Materials, Supplies and Inventory (Details) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Inventory [Line Items]
Fossil Fuel	$ 182,400,000	$ 125,600,000
Materials and Supplies	249,700,000	150,200,000
Natural Gas in Storage	130,400,000	124,800,000
Total	562,500,000	$ 400,600,000
PGL
Inventory [Line Items]
Temporary LIFO liquidation debit	21
NSG
Inventory [Line Items]
Temporary LIFO liquidation credit	$ 5.2

Fair Value Measurements Assets

Fair Value Measurements Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair Value, Assets Measured on Recurring Basis, Derivative Financial Instruments, Assets	$ 3.5	$ 1.1
Fair Value Assets Measured on Recurring Basis Total Assets	3.5	1.1
Fair Value, Liabilities Measured on Recurring Basis, Derivative Financial Instruments, Liabilities	6.7	11.5
Fair Value Liabilities Measured on Recurring Basis Total Liabilities	6.7	11.5
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair Value, Assets Measured on Recurring Basis, Derivative Financial Instruments, Assets	4.1	7.2
Fair Value Assets Measured on Recurring Basis Total Assets	4.1	7.2
Fair Value, Liabilities Measured on Recurring Basis, Derivative Financial Instruments, Liabilities	26.6	1
Fair Value Liabilities Measured on Recurring Basis Total Liabilities	26.6	1
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair Value, Assets Measured on Recurring Basis, Derivative Financial Instruments, Assets	7.7	7
Fair Value Assets Measured on Recurring Basis Total Assets	7.7	7
Fair Value, Liabilities Measured on Recurring Basis, Derivative Financial Instruments, Liabilities	5.4	0
Fair Value Liabilities Measured on Recurring Basis Total Liabilities	5.4	0
Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items]
Fair Value, Assets Measured on Recurring Basis, Derivative Financial Instruments, Assets	15.3	15.3
Fair Value Assets Measured on Recurring Basis Total Assets	15.3	15.3
Fair Value, Liabilities Measured on Recurring Basis, Derivative Financial Instruments, Liabilities	38.7	12.5
Fair Value Liabilities Measured on Recurring Basis Total Liabilities	$ 38.7	$ 12.5

Fair Value Measurements, Deriva

Fair Value Measurements, Derivatives (Details) - Derivative [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Fair value of derivatives classified as Level 3 in the fair value hierarchy
Beginning Balance	$ 3.3	$ 1.7	$ 7	$ 3.5
Realized and unrealized gains (losses)	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	3.9	15.6	3.9	15.6
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(3.6)	(3.2)	(7.3)	(5)
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset and Liability Acquisition of Integrys	(1.3)	0	(1.3)	0
Transfers in and/or out of Level 3	0	0	0	0
Ending Balance	$ 2.3	$ 14.1	$ 2.3	$ 14.1

Fair Value Measurements, Financ

Fair Value Measurements, Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Financial Instruments
Preferred stock of subsidiary	$ 81.5	$ 30.4
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Financial Instruments
Preferred stock of subsidiary	81.5	30.4
Long-term debt including current portion	9,118.4	4,552.4
Estimate of Fair Value, Fair Value Disclosure [Member]
Financial Instruments
Preferred stock of subsidiary	80.1	27.1
Long-term debt including current portion	$ 9,181.1	$ 5,126

Derivative Instruments (Details

Derivative Instruments (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivative asset	$ 15,300,000		$ 15,300,000		$ 15,300,000
Derivative liability	38,700,000		38,700,000		12,500,000
Gains (losses)	(5,000,000)	$ 5,500,000	(10,100,000)	$ 20,300,000
Derivative Instruments (Textuals)
Collateral in margin accounts	26,300,000		26,300,000		11,200,000
Other Deferred Charges and Other Assets [Member]
Derivatives, Fair Value [Line Items]
Long-term portion of derivative assets	1,000,000		1,000,000
Other Deferred Credits and Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Long-term portion of derivative liabilities	5,200,000		5,200,000
Natural Gas [Member]
Derivatives, Fair Value [Line Items]
Derivative asset	6,200,000		6,200,000		5,000,000
Derivative liability	$ 26,900,000		$ 26,900,000		12,300,000
Volume of derivative instruments	10.0 million Dth	9.9 million Dth	23.3 million Dth	24.8 million Dth
Gains (losses)	$ (5,900,000)	$ 2,500,000	$ (13,000,000)	$ 10,100,000
Fuel Oil [Member]
Derivatives, Fair Value [Line Items]
Derivative asset	100,000		100,000		0
Derivative liability	$ 900,000		$ 900,000		0
Volume of derivative instruments	0.8 million gallons	2.4 million gallons	1.7 million gallons	4.4 million gallons
Gains (losses)	$ 100,000	$ 400,000	$ 0	$ 600,000
Ftrs [Member]
Derivatives, Fair Value [Line Items]
Derivative asset	7,700,000		7,700,000		7,000,000
Derivative liability	$ 0		$ 0		0
Volume of derivative instruments	5.9 million MWh	7.4 million MWh	12.1 million MWh	13.1 million MWh
Gains (losses)	$ 800,000	$ 2,600,000	$ 2,900,000	$ 9,600,000
Coal [Member]
Derivatives, Fair Value [Line Items]
Derivative asset	1,300,000		1,300,000		3,300,000
Derivative liability	$ 10,900,000		$ 10,900,000		$ 200,000

Derivative Instruments Derivati

Derivative Instruments Derivative Instruments (Details 1) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Derivative [Member]
Regulatory Assets [Line Items]
Regulatory assets related to derivatives	$ 49.8	$ 14.7

Derivative Instruments Deriva55

Derivative Instruments Derivative Instruments (Details 2) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Derivative [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities related to derivatives	$ 21.6	$ 14.2

Derivative Instruments Deriva56

Derivative Instruments Derivative Instruments (Details 3) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Derivative [Line Items]
Collateral Already Posted, Aggregate Fair Value	$ 26,300,000	$ 11,200,000
Derviative Instrument by Counterparty, Gross Amount Recognized on Balance Sheet [Member]
Derivative [Line Items]
Derivative Assets	(15,300,000)	(15,300,000)
Derivative Liabilities	(38,700,000)	(12,500,000)
Derviative Instrument by Counterparty, Gross Amount Not Offset on Balance Sheet [Member] [Member]
Derivative [Line Items]
Collateral Already Posted, Aggregate Fair Value	3,900,000	10,300,000
Derivative Assets	(4,900,000)	(400,000)
Derivative Liabilities	(8,900,000)	(11,500,000)
Derviative Instrument by Counterparty, Net Amount [Member]
Derivative [Line Items]
Derivative Assets	(10,400,000)	(14,900,000)
Derivative Liabilities	$ (29,800,000)	$ (1,000,000)

Derivative Instruments (Detai57

Derivative Instruments (Details 4) - Jun. 30, 2015 - USD ($) $ in Millions	Total
Derivative [Line Items]
Amount of hedged item deferred into accumulated other comprehensive income	$ 19
Amount of accumulated other comprehensive income reclassified into income	0.1
Amount of accumulated other comprehensive income to be reclassified into income over the next twelve months	1.3
Total senior notes issued in June 2015
Derivative [Line Items]
Issuance of long-term debt related to the acquisition of Integrys	$ 1,200

Guarantees (Details)

Guarantees (Details) $ in Millions	Jun. 30, 2015USD ($)
Guarantees
Total guarantees	$ 276.5
Guarantees expiring in less than 1 year	140.7
Guarantees expiring within 1 to 3 years	0.2
Guarantees with expiration over 3 years	135.6
Guarantees supporting commodity transactions of subsidiaries
Guarantees
Total guarantees	156.4
Guarantees expiring in less than 1 year	83.4
Guarantees expiring within 1 to 3 years	0
Guarantees with expiration over 3 years	73
Guarantees supporting commodity transactions of subsidiaries | WEC Business Support, LLC
Guarantees
Total guarantees	5
Guarantees supporting commodity transactions of subsidiaries | PDL
Guarantees
Total guarantees	6
Guarantees supporting commodity transactions of subsidiaries | ITF
Guarantees
Total guarantees	1.1
Guarantees supporting commodity transactions of subsidiaries | MERC
Guarantees
Total guarantees	109.3
Guarantees supporting commodity transactions of subsidiaries | MGU
Guarantees
Total guarantees	35
Standby letters of credit
Guarantees
Total guarantees	19.9
Guarantees expiring in less than 1 year	19.8
Guarantees expiring within 1 to 3 years	0.1
Guarantees with expiration over 3 years	0
Surety bonds
Guarantees
Total guarantees	33.2
Guarantees expiring in less than 1 year	33.2
Guarantees expiring within 1 to 3 years	0
Guarantees with expiration over 3 years	0
Other guarantees
Guarantees
Total guarantees	67
Guarantees expiring in less than 1 year	4.3
Guarantees expiring within 1 to 3 years	0.1
Guarantees with expiration over 3 years	62.6
Other guarantees | PDL
Guarantees
Total guarantees	34.6
Other guarantees | ITF
Guarantees
Total guarantees	11.2
Other guarantees | Integrys
Guarantees
Total guarantees	10
Other indemnifications primarily for workers compensation coverage
Guarantees
Total guarantees	6.9
Workers compensation obligations
Guarantees
Total guarantees	$ 3.7

Benefits (Details)

Benefits (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Benefits (Textuals) [Abstract]
Pension and Other Postretirement Benefit Contributions			$ 100	$ 0
Estimated liability of Postemployment benefits	$ 7		7		$ 3.3
Pension Plan [Member]
Net Periodic Benefit Cost
Service cost	3.9	$ 2.3	7.8	5
Interest cost	15.1	17	30.3	34.1
Expected return on plan assets	(25.6)	(24.6)	(51.4)	(49.3)
Amortization of:
Prior service cost (credit)	0.5	0.5	1	1
Actuarial loss	11.4	9.3	23	18.4
Net Periodic Benefit Cost	5.3	4.5	10.7	9.2
Other Postretirement Benefit Plan [Member]
Net Periodic Benefit Cost
Service cost	2.1	2.1	4.7	4.3
Interest cost	3.9	4.4	8.1	8.9
Expected return on plan assets	(5.9)	(6)	(11.8)	(11.9)
Amortization of:
Transition obligation	0	0	0	0
Prior service cost (credit)	(0.3)	(0.4)	(0.6)	(0.9)
Actuarial loss	0.5	0.4	1	0.6
Net Periodic Benefit Cost	$ 0.3	$ 0.5	$ 1.4	$ 1

Goodwill (Details)

Goodwill (Details) - Jun. 30, 2015 - USD ($) $ in Millions	Total	Total
Goodwill and Intangible Assets Disclosure [Abstract]
Balance at December 31, 2014		$ 441.9
Acquisition	$ 2,944.6	2,944.6
Balance at June 30, 2015	$ 3,386.5	$ 3,386.5

Investment in ATC - Investment

Investment in ATC - Investment Roll Forward (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 29, 2015	Mar. 31, 2015
Investment in ATC
Equity method investment, ownership interest (as a percent)	60.00%		60.00%		60.00%
Changes to investment in ATC
Add: Earnings from equity method investment	$ 14.2	$ 17.5	$ 30.3	$ 34.8
ATC
Investment in ATC
Equity method investment, ownership interest (as a percent)						26.20%
Changes to investment in ATC
Investment in ATC, balance at beginning of period	431.1	409.6	424.1	402.7
Add: Earnings from equity method investment	14.3	17.5	30.4	34.8
Add: Capital contributions	1.2	3.9	2.5	7.8
Add: Acquisition of Integrys equity in ATC	552	0	552	0
Less: Distributions received	10.8	14.2	21.2	28.5
Investment in ATC, balance at end of period	$ 987.8	$ 416.8	$ 987.8	$ 416.8

Investment in ATC - ATC Income

Investment in ATC - ATC Income Statement and Balance Sheet (Details) - ATC - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Income statement data
Revenues	$ 165.2	$ 160	$ 317.5	$ 323.3
Operating expenses	80.3	74.4	160.3	153
Other expense	24.3	21.9	48.6	43.5
Net income	60.6	$ 63.7	108.6	$ 126.8
Balance sheet data
Current assets	78.1		78.1		$ 66.4
Noncurrent assets	3,835.2		3,835.2		3,728.7
Total assets	3,913.3		3,913.3		3,795.1
Current liabilities	255.7		255.7		313.1
Long-term debt	1,800		1,800		1,701
Other noncurrent liabilities	197.7		197.7		163.8
Shareholders' equity	1,659.9		1,659.9		1,617.2
Total liabilities and shareholders' equity	$ 3,913.3		$ 3,913.3		$ 3,795.1

Segment Information (Details)

Segment Information (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Financial information of reportable operating segments
Operating Revenues	[1]	$ 991.2	$ 1,043.7	$ 2,379.1	$ 2,738.7
Other operation and maintenance		337	256	617.7	531.4
Depreciation and Amortization		105.7	101.4	210.8	202
Operating Income (Loss)		165.8	240.7	524.6	622.5
Equity in Earnings of Unconsolidated Affiliates		14.2	17.5	30.3	34.8
Interest Expense, net		62.1	59	121.8	121.3
Income Tax Expense (Benefit)		63.2	74.3	185.6	204.6
Net Income (Loss)		80.9	133	276.7	340.6
Capital Expenditures		207	176.3	356.5	305.5
Reportable Operating Segments Energy Utility [Member]
Financial information of reportable operating segments
Operating Revenues	[1]	979.9	1,029.8	2,356.8	2,711.9
Other operation and maintenance		368.3	343.6	737.4	711.2
Depreciation and Amortization		88.5	84.3	176.4	167.9
Operating Income (Loss)		140.4	155.2	416.9	447.9
Equity in Earnings of Unconsolidated Affiliates		14.3	17.5	30.4	34.8
Interest Expense, net		32.4	30.7	64.1	64.7
Income Tax Expense (Benefit)		44	51.4	141.8	158.8
Net Income (Loss)		82.1	96.3	247.2	265.7
Capital Expenditures		201	172.6	345.2	293.3
Reportable Operating Segments Energy Non Utility [Member]
Financial information of reportable operating segments
Operating Revenues	[1]	115.3	113.4	225	221.7
Other operation and maintenance		4.7	5	5.8	6.2
Depreciation and Amortization		17.1	16.7	34.1	33.6
Operating Income (Loss)		93.5	91.7	185.1	181.9
Equity in Earnings of Unconsolidated Affiliates		0	0	0	0
Interest Expense, net		15.9	16.2	31.8	32.5
Income Tax Expense (Benefit)		38.4	30.2	69	60.2
Net Income (Loss)		39.5	45.4	84.7	89.5
Capital Expenditures		3.2	4.6	7.2	9.7
Corporate and Other [Member]
Financial information of reportable operating segments
Operating Revenues	[1],[2]	0.5	0.3	0.8	0.6
Other operation and maintenance	[2]	68.1	6.1	77.5	7.3
Depreciation and Amortization	[2]	0.1	0.4	0.3	0.5
Operating Income (Loss)	[2]	(68.1)	(6.2)	(77.4)	(7.3)
Equity in Earnings of Unconsolidated Affiliates	[2]	(0.1)	0	(0.1)	0
Interest Expense, net	[2]	14	12.2	26.2	24.4
Income Tax Expense (Benefit)	[2]	(19.2)	(7.3)	(25.2)	(14.4)
Net Income (Loss)	[2]	82.1	132.9	279.1	340.4
Capital Expenditures	[2]	2.8	(0.9)	4.1	2.5
Eliminations and Reconciling Items [Member]
Financial information of reportable operating segments
Operating Revenues	[1]	(104.5)	(99.8)	(203.5)	(195.5)
Other operation and maintenance		(104.1)	(98.7)	(203)	(193.3)
Depreciation and Amortization		0	0	0	0
Operating Income (Loss)		0	0	0	0
Equity in Earnings of Unconsolidated Affiliates		0	0	0	0
Interest Expense, net		(0.2)	(0.1)	(0.3)	(0.3)
Income Tax Expense (Benefit)		0	0	0	0
Net Income (Loss)		(122.8)	(141.6)	(334.3)	(355)
Capital Expenditures		$ 0	$ 0	$ 0	$ 0
[1]	An elimination for intersegment revenues is included in Operating Revenues. This elimination is primarily between We Power and Wisconsin Electric.
[2]	Corporate & Other includes all other non-utility activities, primarily non-utility real estate investment and development by Wispark LLC, as well as interest on corporate debt.

Variable Interest Entities (Det

Variable Interest Entities (Details) $ in Millions	6 Months Ended
	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)
Variable Interest Entities (Textuals)
Power capacity under capital lease (MW)	236
Capital Lease Agreement With Vie Remaining Term In Years	7 years
Total payments over remaining terms of the agreement	$ 152.2
Total capacity and lease payments	$ 26.8	$ 26.7

Commitments and Contingencies65

Commitments and Contingencies (Details) - Manufactured Gas Plant Sites - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Loss Contingencies [Line Items]
Regulatory Assets	$ 670.7	$ 45.9
Reserves for Future Remediation	$ 608.6	$ 32.6

Supplemental Cash Flow Inform66

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Supplemental Cash Flow Information (Textuals)
Interest paid, net of amounts capitalized			$ 116.9	$ 122.4
Income Taxes Paid, Net			3	17.6
Accounts payable related to capital expenditures	$ 3.5	$ 3.2	3.5	3.2
Amortization of deferred revenue			20.7	27.8
Equity in Earnings of Unconsolidated Affiliates	14.2	17.5	30.3	34.8
Transmission Affiliate [Member]
Supplemental Cash Flow Information (Textuals)
Equity in Earnings of Unconsolidated Affiliates	14.3	17.5	30.4	34.8
Distributions from transmission affiliate	$ 10.8	$ 14.2	$ 21.2	$ 28.5