| **PROPOSED MERGER WITH AGL RESOURCES**            | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     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| **PROPOSED MERGER WITH AGL RESOURCES [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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| PROPOSED MERGER WITH AGL RESOURCES                | 1.PROPOSED MERGER WITH AGL RESOURCES In December 2010, Nicor entered into an Agreement and Plan of Merger (the “Merger Agreement”) with AGL Resources, which Nicor expects will be complete in the fourth quarter of 2011.  In accordance with the Merger Agreement, each share of Nicor common stock outstanding at the Effective Time (as defined in the Merger Agreement), other than shares to be cancelled and Dissenting Shares (as defined in the Merger Agreement), will be converted into the right to receive consideration consisting of (i) $21.20 in cash and (ii) 0.8382 shares of AGL Resources common stock, subject to adjustments in certain circumstances. Completion of the proposed merger is conditioned upon, among other things, shareholder approval by both companies and the receipt of various regulatory approvals.  AGL Resources filed a registration statement with the SEC to register the AGL Resources common stock to be issued in the merger, and the SEC permitted that registration to become effective on April 29, 2011.  AGL Resources and Nicor also filed their pre-merger notifications under the Hart-Scott-Rodino Antitrust Improvements Act and were granted early termination of the waiting period on April 18, 2011.  The approvals from Nicor shareholders and AGL Resources shareholders required in connection with the merger were received on June 14, 2011. In January 2011, Nicor, Nicor Gas and AGL Resources filed a joint application with the ICC for approval of the proposed merger.  The approval by the ICC is a condition to completion of the merger.  The ICC has eleven months to act upon the application, with their statutory deadline for action being December 16, 2011.  The application did not request a rate increase and included a commitment to maintain the number of full-time equivalent employees involved in the operation of Nicor Gas at a level comparable to current staffing for a period of three years following merger completion.  The Staff of the ICC and several intervenors who are participating in the proceeding submitted testimony and legal briefs, recommending that the ICC deny the joint application or that it impose various requirements on the joint applicants as conditions of approval.  On September 29, 2011, the ALJ assigned by the ICC to preside over the proceeding issued a proposed order recommending approval of the proposed merger.  The ALJ also recommended imposing the condition that Nicor Gas no longer be permitted to provide sales solicitation for Nicor Services’ warranty products.  On October 13, 2011, briefs were filed to comment on the proposed order.  Testimony and legal briefs of the parties and the ALJ’s proposed order are available on the ICC’s website.  In ruling on the merger application, the ICC may accept, modify or reject the proposed order recommended by the ALJ. The merger may also be subject to review by the governmental authorities of various other federal, state or local jurisdictions under the antitrust and utility regulation or other applicable laws of those jurisdictions.  For example, AGL Resources provided a voluntary notice of the merger to the New Jersey Board of Public Utilities (“NJBPU”), which included a description of the transaction, described the benefits of the transaction and explained why AGL Resources does not believe that the approval of the NJBPU is required to complete the merger.  AGL Resources provided a similar notice to the Maryland Public Service Commission, which then issued a letter stating that it had reviewed the notification of proposed merger filed by AGL Resources and after considering the matter, noted the transaction.  It is possible that one or more state commissions will open proceedings to determine whether they have jurisdiction over the merger.  In the event that any reviewing authorities are determined to have jurisdiction over the merger transaction, there can be no assurance that the reviewing authorities will permit the applicable statutory waiting periods to expire or that the reviewing authorities will terminate the applicable statutory waiting periods at all, or otherwise approve the merger without restrictions or conditions (which are difficult to predict or quantify) that would have a material adverse effect on the combined company if the merger were completed. The Merger Agreement contains certain termination rights for both Nicor and AGL Resources, and further provides for the payment of fees and expenses upon termination under specified circumstances.  For additional information relating to the proposed merger, please see the joint proxy statement / prospectus contained in the registration statement on Form S-4 that was filed with the SEC by AGL Resources on April 29, 2011. For the three and nine months ended September 30, 2011, the company has incurred and expensed approximately $0.4 million and $2.8 million, respectively, of merger transaction costs.  These amounts do not include the cost of company personnel participating in efforts to develop integration plans for the combined entity which are included in operating expenses of the respective companies.  No other adjustments have been made to the financial statements as a result of the proposed merger. |

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The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).
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