XML 132 R117.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Other, Net (Schedule Of Other Net) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Other Nonoperating Income (Expense) [Abstract] |  |  |  |  |  |  |  |
Interest income |  |  | $ 6.6 |  | $ 4.6 |  | $ 3.4 |
AFUDC Equity |  |  | 14.2 |  | 12.6 |  | 11.6 |
Charitable Contributions |  | $ 20.7 | (45.3) | [1] | (19.9) | [1] | (4.5) | [1]
Pension and Other Postretirement Non Service Cost | [2] |  | 18.0 |  | (10.6) |  | (7.9) |
Interest rate swap settlement gain | [3] |  |  |  | 0.0 |  | 0.0 |
Miscellaneous |  |  | 3.8 |  | (0.2) |  | (5.6) |
Total Other, net |  |  | $ 43.5 |  | $ (13.5) |  | $ (3.0) |
[1] | Includes $20.7 million related to the Greater Lawrence Incident. See Note 18, "Other Commitments and Contingencies" for additional information.
[2] | See Note 11, "Pension and Other Postretirement Benefits" for additional information.
[3] | See Note 9, "Risk Management Activities" for additional information.

X
- Definition Charitable contributions included in other, net + References No definition available. + Details
Name: | nix_CharitableContributions
Namespace Prefix: | nix_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Miscellaneous Non-Operating Income (Expense) + References No definition available. + Details
Name: | nix_MiscellaneousNonOperatingIncomeExpense
Namespace Prefix: | nix_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Pension and Other Postretirement Non Service Cost + References No definition available. + Details
Name: | nix_PensionandOtherPostretirementNonServiceCost
Namespace Prefix: | nix_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(h)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details
Name: | us-gaap_GainLossOnSaleOfDerivatives
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The net amount of nonoperating interest income (expense). + References No definition available. + Details
Name: | us-gaap_InterestIncomeExpenseNonoperatingNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of income (expense) related to nonoperating activities, classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.9) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
Name: | us-gaap_OtherNonoperatingIncomeExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_OtherNonoperatingIncomeExpenseAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount capitalized of allowance for funds used during construction. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 835 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501569&loc=d3e55921-110430 + Details
Name: | us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration