v2.4.0.8

Long-Term Debt (Narrative) (Details) (USD $) In Millions, unless otherwise specified |  | 0 Months Ended | 2 Months Ended | 0 Months Ended |  |
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Jun. 03, 2013 Northern Indiana [Member] Pollution Control Bond [Member] | Apr. 12, 2013 NiSource Finance [Member] 4.80% Senior Unsecured Notes Due February 15, 2044 [Member] | Mar. 01, 2013 NiSource Finance [Member] 6.15% Notes Due 2013 [Member] | Apr. 15, 2013 NiSource Finance [Member] LIBOR plus 125 basis points three-year bank term loan due April 15, 2016 | Apr. 05, 2012 NiSource Finance [Member] LIBOR plus 125 basis points three-year bank term loan due April 15, 2016 | Apr. 05, 2012 NiSource Finance [Member] Previous Maximum [Member] LIBOR plus 125 basis points three-year bank term loan due April 15, 2016 | Apr. 15, 2013 NiSource Finance [Member] Current Maximum [Member] LIBOR plus 125 basis points three-year bank term loan due April 15, 2016
Debt Instrument [Line Items] |  |  |  |  |  |  |
Face amount of notes | $ 18.0 | $ 750.0 |  |  |  | $ 250.0 | $ 325.0
Debt instrument maturity date |  | Feb. 15, 2044 |  | Apr. 15, 2016 | Apr. 03, 2015 |  |
Repayments of Senior Debt |  |  | $ 420.3 |  |  |  |
Interest rate on debt | 5.20% | 4.80% | 6.15% |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  | 1.25% |  |  |
Long term debt note term |  |  |  | 3 years |  |  |

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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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