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Other Commitments And Contingencies (Narrative) (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 USD ($) | Mar. 31, 2016 USD ($) | Dec. 31, 2016 USD ($)
Other Commitments And Contingencies [Line Items] |  |  |
Proposed Pipeline Safety Rule, time period for investigation and repair/replace activity on facilities | 15 years |  |
Recorded reserves to cover environmental remediation at various sites | $ 109.3 |  | $ 111.4
Estimated Cost of Compliance with Coal Combustion Residuals, Maximum | 230.0 |  |
Estimated Cost of Compliance with Effluent Limitations Guidelines | $ 170.0 |  |
Transmission Upgrade Agreement Multiplier | 1.71 |  |
Liability Associated with Bailey Generating Station Retirement |  |  | 22.1
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount | $ 0.0 |  |
Payments Pure Air | 5.5 | $ 4.9 |
Liability Associated with Bailly Generating Station Retirement - Pure Air Contract Termination Portion | $ 16.0 |  |
MGP Sites |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Number of waste disposal sites identified by program | 64 |  |
Liability for Estimated Remediation Costs | $ 103.9 |  | 105.5
Reasonably possible remediation costs variance from reserve | $ 25.0 |  |
NIPSCO |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Upgrade Sponsors Liability related to Portion Collected for Taxes on TUA |  |  | 8.6
Maximum |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Ozone Level | 75 ppb |  |
Minimum |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Ozone Level | 70 ppb |  |
Minimum | NIPSCO |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Cost to Maintain and Operate Current Fleet of Coal-Fired Generating Units | $ 1,000.0 |  |
Standby Letters of Credit |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Long-term Line of Credit | $ 14.7 |  | $ 14.7

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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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