Variable Interests and Variable Interest Entities	6 Months Ended
Jun. 30, 2015
Variable Interest Entities And Equity Investments [Abstract]
Variable Interests and Variable Interest Entities	Variable Interests and Variable Interest Entities In general, a VIE is an entity that (1) has an insufficient amount of at-risk equity to permit the entity to finance its activities without additional financial subordinated support provided by any parties, (2) whose at-risk equity owners, as a group, do not have power, through voting rights or similar rights, to direct activities of the entity that most significantly impact the entity’s economic performance or (3) whose at-risk owners do not absorb the entity’s losses or receive the entity’s residual return. A VIE is required to be consolidated by a company if that company is determined to be the primary beneficiary of the VIE. NiSource consolidates those VIEs for which it is the primary beneficiary. NiSource considers quantitative and qualitative elements in determining the primary beneficiary. Qualitative measures include the ability to control an entity and the obligation to absorb losses or the right to receive benefits. NiSource’s analysis includes an assessment of guarantees, operating leases, purchase agreements, and other contracts, as well as its investments and joint ventures. For items that have been identified as variable interests, or where there is involvement with an identified VIE, an in-depth review of the relationship between the relevant entities and NiSource is made to evaluate qualitative and quantitative factors to determine the primary beneficiary, if any, and whether additional disclosures would be required under the current standard. NIPSCO has a service agreement with Pure Air, a general partnership between Air Products and Chemicals, Inc. and First Air Partners LP, under which Pure Air provides scrubber services to reduce sulfur dioxide emissions for Units 7 and 8 at the Bailly Generating Station. NiSource has made an exhaustive effort to obtain information needed from Pure Air to determine the status of Pure Air as a VIE. However, NIPSCO has not been able to obtain this information and, as a result, it is unclear whether Pure Air is a VIE and if NIPSCO is the primary beneficiary. NIPSCO will continue to request the information required to determine whether Pure Air is a VIE. NIPSCO has no exposure to loss related to the service agreement with Pure Air. Payments under this agreement were $10.7 million and $10.6 million for the six months ended June 30, 2015 and 2014, respectively.

Variable Interests and Variable Interest Entities

In general, a VIE is an entity that (1) has an insufficient amount of at-risk equity to permit the entity to finance its activities without additional financial subordinated support provided by any parties, (2) whose at-risk equity owners, as a group, do not have power, through voting rights or similar rights, to direct activities of the entity that most significantly impact the entity’s economic performance or (3) whose at-risk owners do not absorb the entity’s losses or receive the entity’s residual return. A VIE is required to be consolidated by a company if that company is determined to be the primary beneficiary of the VIE.

NiSource consolidates those VIEs for which it is the primary beneficiary. NiSource considers quantitative and qualitative elements in determining the primary beneficiary. Qualitative measures include the ability to control an entity and the obligation to absorb losses or the right to receive benefits.

NiSource’s analysis includes an assessment of guarantees, operating leases, purchase agreements, and other contracts, as well as its investments and joint ventures. For items that have been identified as variable interests, or where there is involvement with an identified VIE, an in-depth review of the relationship between the relevant entities and NiSource is made to evaluate qualitative and quantitative factors to determine the primary beneficiary, if any, and whether additional disclosures would be required under the current standard.

NIPSCO has a service agreement with Pure Air, a general partnership between Air Products and Chemicals, Inc. and First Air Partners LP, under which Pure Air provides scrubber services to reduce sulfur dioxide emissions for Units 7 and 8 at the Bailly Generating Station. NiSource has made an exhaustive effort to obtain information needed from Pure Air to determine the status of Pure Air as a VIE. However, NIPSCO has not been able to obtain this information and, as a result, it is unclear whether Pure Air is a VIE and if NIPSCO is the primary beneficiary. NIPSCO will continue to request the information required to determine whether Pure Air is a VIE. NIPSCO has no exposure to loss related to the service agreement with Pure Air. Payments under this agreement were $10.7 million and $10.6 million for the six months ended June 30, 2015 and 2014, respectively.