v2.4.0.8

Asset Retirement Obligations (Tables) | 6 Months Ended
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Jun. 30, 2013
Asset Retirement Obligation [Abstract] |
Changes In Company's Liability For Asset Retirement Obligations | Changes in NiSource’s liability for asset retirement obligations for the six months ended June 30, 2013 and 2012 are presented in the table below:
(in millions) | 2013 |  | 2012
Balance as of January 1, | $ | 160.4 |  |  | $ | 146.4 |
Accretion expense | 0.6 |  |  | 0.5 |
Accretion recorded as a regulatory asset/liability | 4.4 |  |  | 4.3 |
Additions | 3.0 |  |  | — |
Settlements | (0.6 | ) |  | (1.5 | )
Change in estimated cash flows | (0.7 | ) |  | — |
Balance as of June 30, | $ | 167.1 |  |  | $ | 149.7 |

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