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v3.20.4

Long-Term Debt (Schedule of Consolidated Long-Term Debt (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Debt Instrument [Line Items] |  |
Senior Notes | $ 9,003.0 | $ 7,581.6
Medium-Term Notes | 132.0 | 157.0
Capital Lease Obligations | 195.0 | 201.5
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net | (86.9) | (70.5)
Long-term Debt, Excluding Current Maturities | $ 9,243.1 | 7,869.6
NiSource | 4.45% Notes Due 2021 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Dec. 31, 2021 |
Debt, Weighted Average Interest Rate | 4.45% |
Senior Notes | $ 0.0 | 63.6
NiSource | 2.65% Notes Due 2022 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Nov. 30, 2022 |
Debt, Weighted Average Interest Rate | 2.65% |
Senior Notes | $ 0.0 | 500.0
NiSource | 3.85% Notes Due 2023 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Feb. 28, 2023 |
Debt, Weighted Average Interest Rate | 3.85% |
Senior Notes | $ 0.0 | 250.0
NiSource | 3.65% Notes Due 2023 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Jun. 30, 2023 |
Debt, Weighted Average Interest Rate | 3.65% |
Senior Notes | $ 0.0 | 350.0
NiSource | 0.95% Notes Due 2025 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 0.95% |
Senior Notes | $ 1,250.0 | 0.0
NiSource | 5.89% Notes Due 2025 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Nov. 30, 2025 |
Debt, Weighted Average Interest Rate | 5.89% |
Senior Notes | $ 0.0 | 265.0
NiSource | 3.49% Notes due 2027 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | May 31, 2027 |
Debt, Weighted Average Interest Rate | 3.49% |
Senior Notes | $ 1,000.0 | 1,000.0
NiSource | 6.78% Notes Due 2027 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Dec. 31, 2027 |
Debt, Weighted Average Interest Rate | 6.78% |
Senior Notes | $ 3.0 | 3.0
NiSource | 2.95% Notes Due 2029 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Sep. 30, 2029 |
Debt, Weighted Average Interest Rate | 2.95% |
Senior Notes | $ 750.0 | 750.0
NiSource | 3.60% Notes Due 2030 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 3.60% |
Senior Notes | $ 1,000.0 | 0.0
NiSource | 1.70% Notes Due 2031 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 1.70% |
Senior Notes | $ 750.0 | 0.0
NiSource | 6.25% Notes Due 2040 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Dec. 31, 2040 |
Debt, Weighted Average Interest Rate | 6.25% |
Senior Notes | $ 152.6 | 250.0
NiSource | 5.95% Notes Due 2041 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Jun. 30, 2041 |
Debt, Weighted Average Interest Rate | 5.95% |
Senior Notes | $ 347.4 | 400.0
NiSource | 5.80% Notes Due 2042 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Feb. 28, 2042 |
Debt, Weighted Average Interest Rate | 5.80% |
Senior Notes | $ 250.0 | 250.0
NiSource | 5.25% Notes Due 2043 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Feb. 28, 2043 |
Debt, Weighted Average Interest Rate | 5.25% |
Senior Notes | $ 500.0 | 500.0
NiSource | 4.80% Notes due 2044 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Feb. 29, 2044 |
Debt, Weighted Average Interest Rate | 4.80% |
Senior Notes | $ 750.0 | 750.0
NiSource | 5.65% Notes Due 2045 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Feb. 28, 2045 |
Debt, Weighted Average Interest Rate | 5.65% |
Senior Notes | $ 500.0 | 500.0
NiSource | 4.375% Notes due 2047 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | May 31, 2047 |
Debt, Weighted Average Interest Rate | 4.38% |
Senior Notes | $ 1,000.0 | 1,000.0
NiSource | 3.95% Notes Due 2048 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Mar. 31, 2048 |
Debt, Weighted Average Interest Rate | 3.95% |
Senior Notes | $ 750.0 | 750.0
NiSource | 7.99% Notes Due 2027 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 7.99% |
Medium-Term Notes | $ 49.0 | $ 49.0
NiSource | 7.99% Notes Due 2027 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | May 31, 2027 |
NiSource | 7.99% Notes Due 2027 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Apr. 30, 2022 |
Columbia Of Massachusetts | 6.30% Notes Due 2028 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 6.37% | 630.00%
Medium-Term Notes | $ 15.0 | $ 40.0
Columbia Of Massachusetts | 6.30% Notes Due 2028 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Feb. 28, 2028 |
Columbia Of Massachusetts | 6.30% Notes Due 2028 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Dec. 31, 2025 |
Columbia Of Massachusetts | 5.49% notes Due 2043 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 0.00% |
Capital Lease Obligations | $ 0.0 | 44.3
Columbia Of Massachusetts | 5.49% notes Due 2043 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Nov. 30, 2043 |
Columbia Of Massachusetts | 5.49% notes Due 2043 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Dec. 31, 2033 |
NIPSCO | 7.61% Notes Due 2027 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 7.61% |
Medium-Term Notes | $ 68.0 | 68.0
NIPSCO | 7.61% Notes Due 2027 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Aug. 31, 2027 |
NIPSCO | 7.61% Notes Due 2027 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Aug. 31, 2022 |
NIPSCO | 1.79% Notes Due 2028 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 1.79% |
Capital Lease Obligations | $ 16.0 | 0.0
NIPSCO | 5.85% Notes Due 2019 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Apr. 30, 2019 |
Columbia Of Ohio | 6.16% Notes Due 2044 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 6.16% |
Capital Lease Obligations | $ 91.2 | 94.8
Columbia Of Ohio | 6.16% Notes Due 2044 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Mar. 31, 2044 |
Columbia Of Ohio | 6.16% Notes Due 2044 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Oct. 31, 2021 |
NiSource Corporate Services | 3.47% Notes Due 2023 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 2.19% |
Capital Lease Obligations | $ 49.4 | 22.3
NiSource Corporate Services | 3.47% Notes Due 2023 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Nov. 30, 2023 |
NiSource Corporate Services | 3.47% Notes Due 2023 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Jan. 31, 2020 |
Columbia Of Virginia | 6.31% Notes Due 2039 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 6.30% |
Capital Lease Obligations | $ 18.4 | 19.1
Columbia Of Virginia | 6.31% Notes Due 2039 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Nov. 30, 2039 |
Columbia Of Virginia | 6.31% Notes Due 2039 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Jul. 31, 2029 |
Columbia Of Kentucky | 3.79% Notes Due 2027 |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | May 31, 2027 |
Debt, Weighted Average Interest Rate | 3.79% |
Capital Lease Obligations | $ 0.3 | 0.3
Columbia Of Pennsylvania | 5.67% Notes Due 2035 |  |
Debt Instrument [Line Items] |  |
Debt, Weighted Average Interest Rate | 5.65% |
Capital Lease Obligations | $ 19.7 | $ 20.7
Columbia Of Pennsylvania | 5.67% Notes Due 2035 | Maximum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | May 31, 2035 |
Columbia Of Pennsylvania | 5.67% Notes Due 2035 | Minimum |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Date | Aug. 31, 2027 |

X
- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -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=120391452&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121616839&loc=d3e45280-112737 + Details
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -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=120398452&loc=d3e534808-122878 + Details
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