v2.4.0.8

Fair Value Disclosures (Tables) | 6 Months Ended
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Jun. 30, 2013
Fair Value Disclosures [Abstract] |
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis | The following tables present financial assets and liabilities measured and recorded at fair value on NiSource’s Condensed Consolidated Balance Sheets (unaudited) on a recurring basis and their level within the fair value hierarchy as of June 30, 2013 and December 31, 2012:
Recurring Fair Value Measurements June 30, 2013 (in millions) | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Balance as of June 30, 2013
Assets |  |  |  |  |  |  |
Commodity Price risk management assets: |  |  |  |  |  |  |
Physical price risk programs | $ | — |  |  | $ | 14.6 |  |  | $ | — |  |  | $ | 14.6 |
Financial price risk programs | 27.6 |  |  | 0.4 |  |  | — |  |  | 28.0 |
Interest rate risk activities | — |  |  | 30.9 |  |  | — |  |  | 30.9 |
Available-for-sale securities | 22.4 |  |  | 86.2 |  |  | — |  |  | 108.6 |
Total | $ | 50.0 |  |  | $ | 132.1 |  |  | $ | — |  |  | $ | 182.1 |
Liabilities |  |  |  |  |  |  |
Commodity Price risk management liabilities: |  |  |  |  |  |  |
Physical price risk programs | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Financial price risk programs | 51.3 |  |  | 0.2 |  |  | 1.0 |  |  | 52.5 |
Total | $ | 51.3 |  |  | $ | 0.2 |  |  | $ | 1.0 |  |  | $ | 52.5 |
Recurring Fair Value Measurements December 31, 2012 (in millions) | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Balance as of December 31, 2012
Assets |  |  |  |  |  |  |
Commodity Price risk management assets: |  |  |  |  |  |  |
Physical price risk programs | $ | — |  |  | $ | 35.4 |  |  | $ | — |  |  | $ | 35.4 |
Financial price risk programs | 71.5 |  |  | 0.8 |  |  | 0.1 |  |  | 72.4 |
Interest rate risk activities | — |  |  | 40.4 |  |  | — |  |  | 40.4 |
Available-for-sale securities | 27.4 |  |  | 84.4 |  |  | — |  |  | 111.8 |
Total | $ | 98.9 |  |  | $ | 161.0 |  |  | $ | 0.1 |  |  | $ | 260.0 |
Liabilities |  |  |  |  |  |  |
Commodity Price risk management liabilities: |  |  |  |  |  |  |
Physical price risk programs | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Financial price risk programs | 115.0 |  |  | 0.5 |  |  | — |  |  | 115.5 |
Total | $ | 115.0 |  |  | $ | 0.5 |  |  | $ | — |  |  | $ | 115.5 |
Available-For-Sale Debt Securities | The amortized cost, gross unrealized gains and losses, and fair value of available-for-sale debt securities at June 30, 2013 and December 31, 2012 were:
(in millions) | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Value
Available-for-sale debt securities, June 30, 2013 |  |  |  |  |  |  |
U.S. Treasury | $ | 27.5 |  |  | $ | 0.4 |  |  | $ | (0.8 | ) |  | $ | 27.1 |
Corporate/Other | 82.2 |  |  | 0.9 |  |  | (1.6 | ) |  | 81.5 |
Total Available-for-sale debt securities | $ | 109.7 |  |  | $ | 1.3 |  |  | $ | (2.4 | ) |  | $ | 108.6 |
(in millions) | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Fair Value
Available-for-sale debt securities, December 31, 2012 |  |  |  |  |  |  |
U.S. Treasury | $ | 31.1 |  |  | $ | 1.5 |  |  | $ | — |  |  | $ | 32.6 |
Corporate/Other | 76.8 |  |  | 2.5 |  |  | (0.1 | ) |  | 79.2 |
Total Available-for-sale debt securities | $ | 107.9 |  |  | $ | 4.0 |  |  | $ | (0.1 | ) |  | $ | 111.8 |
Carrying Amount And Estimated Fair Values Of Financial Instruments |
(in millions) | Carrying Amount as of June 30, 2013 |  | Estimated Fair Value as of June 30, 2013 |  | Carrying Amount as of Dec. 31, 2012 |  | Estimated Fair Value as of Dec. 31, 2012
Long-term debt (including current portion) | $ | 7,687.4 |  |  | $ | 8,296.2 |  |  | $ | 7,326.3 |  |  | $ | 8,389.0 |

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- Definition Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27198-111563 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19190-110258 + Details
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