Description of Business	12 Months Ended
Dec. 31, 2012
Description of Business
Description of Business	(1) Description of Business Envirocare of Utah, Inc. (predecessor) was formed in 1988 to operate a disposal facility for mixed waste, uranium mill tailings and Class A low-level radioactive waste ("LLRW") in Clive, Utah. In January 2005, the predecessor converted to a limited liability company, Envirocare of Utah, LLC ("Envirocare"). Immediately thereafter, the sole member of Envirocare sold all of its member interest to ENV Holdings LLC ("ENV Holdings"). In 2006, we changed our name from Envirocare of Utah, LLC to EnergySolutions, LLC ("we," "our," "EnergySolutions" or the "Company"). Since 2005, we have expanded and diversified our operations through a series of strategic acquisitions, including the decontamination and decommissioning ("D&D") division of Scientech, LLC ("Scientech") in October 2005, BNG America, LLC ("BNGA") in February 2006, Duratek, Inc. ("Duratek") in June 2006, Safeguard International Solutions, Ltd. (renamed ESEU Services Limited ("ESEU")) in December 2006, Parallax, Inc. (renamed EnergySolutions Performance Strategies) in January 2007, Reactor Sites Management Company Limited ("RSMC") in June 2007, NUKEM Corporation (renamed EnergySolutions Diversified Services, Inc.) in July 2007, and Monserco Limited ("Monserco") in December 2007. On November 20, 2007, the date of the completion of our initial public offering, we completed our conversion to a corporate structure whereby EnergySolutions, LLC became a wholly owned subsidiary of EnergySolutions, Inc. As a result, the member of EnergySolutions, LLC contributed its membership equity interest for 75.2 million shares of $0.01 par value common stock of EnergySolutions, Inc. EnergySolutions, Inc., is organized and existing under the General Corporation Law of the state of Delaware. On July 30, 2008, we completed a secondary public offering of 35 million shares of common stock offered by ENV Holdings, as selling stockholder. The underwriters of the offering subsequently exercised their over-allotment option and purchased 5.25 million additional shares of our common stock from ENV Holdings. Following completion of these transactions, ENV Holdings owned approximately 16.7% of our outstanding shares of common stock. We did not receive any proceeds from the sale of shares by ENV Holdings and recognized expenses of $1.8 million for the year ended December 31, 2008. On February 13, 2009, ENV Holdings completed a distribution of all of our shares to its members on a pro rata basis for no consideration. As a result, ENV Holdings is no longer the beneficial owner, directly or indirectly, of any shares of our common stock. On January 7, 2013, we entered into an Agreement and Plan of Merger (the "Merger Agreement") with Rockwell Holdco, Inc., a Delaware corporation ("Parent"), and Rockwell Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger Sub"). Parent and Merger Sub are affiliates of Energy Capital Partners II, LP and its parallel funds (together with its affiliates, "Energy Capital Partners"), a leading private equity firm focused on investing in North America's energy infrastructure. Pursuant to the Merger Agreement, the Merger Sub will merge with and into the Company (the "Merger") and we will become a wholly-owned subsidiary of Parent. The Merger will only be able to be consummated after the stockholders of the Company have adopted the Merger Agreement at a meeting of stockholders and following the satisfaction or waiver of a number of conditions set forth in the Merger Agreement. Upon completion of the Merger, each outstanding share of the Company's common stock other than shares of common stock held in the treasury of the Company or owned by Parent, any affiliates of Parent, Merger Sub, a subsidiary of the Company or by stockholders who have validly exercised their appraisal rights under Delaware law, will be converted into the right to receive cash in an amount equal to $3.75, without interest and subject to any required withholding of taxes. The obligation of Parent and Merger Sub to consummate the Merger is subject to the satisfaction or waiver of a number of conditions set forth in the Merger Agreement, including (i) the adoption of the Merger Agreement and approval of the transactions contemplated thereby by stockholders of the Company owning at least a majority of outstanding shares of the Company's common stock, (ii) the expiration or termination of any applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act"), (iii) a notification from the Committee on Foreign Investment in the United States ("CFIUS") that it has determined not to investigate the transactions contemplated in the Merger Agreement, but only if the Company and Parent have elected to make a filing to CFIUS, (iv) the absence of any law or order preventing the consummation of the Merger, (v) the obtaining of certain regulatory approvals, including approval from the NRC and consent from the NDA, (vi) subject to certain exceptions, the accuracy of the Company's representations and warranties, (vii) the Company's compliance in all material respect with its obligations under the Merger Agreement and (viii) the absence of a material adverse effect on the Company. The early termination of the waiting period under the HSR Act was granted and became effective on February 1, 2013. The Company submitted the formal consent application to the NDA on January 21, 2013. The NDA, in a letter dated January 24, 2013, gave its consent to the change in control of EnergySolutions EU Limited in satisfaction of this aspect of the Merger Agreement. Also, the Company and Parent determined not to make a filing with CFIUS pursuant to the Defense Protection Act of 1950, based on their belief that no such filing is necessary with respect to the transactions contemplated by the Merger Agreement. We report our results through two major operating groups: the Government Group and the Global Commercial Group. The Government Group derives its revenue from United States ("U.S.") government customers for the management and operation or clean-up of facilities with radioactive materials. Our U.S. government customers are primarily individual offices, departments and administrations within the U.S. Department of Energy ("DOE") and U.S. Department of Defense ("DOD"). The Global Commercial Group provides a broad range of services both nationally and internationally, including (i) on-site D&D services to commercial customers such as power and utility companies, pharmaceutical companies, research laboratories, universities, industrial facilities, state agencies and other commercial entities that are involved with nuclear materials; (ii) logistics, transportation, processing and disposal services to both government and commercial customers at our facility in Clive, Utah, our four facilities in Tennessee, or our two facilities in Barnwell, South Carolina; and (iii) comprehensive long-term stewardship D&D work for shut-down nuclear power plants and similar operations. Our international operations derive revenue primarily through contracts with the Nuclear Decommissioning Authority ("NDA") in the United Kingdom ("U.K.") to operate, manage and decommission ten Magnox sites with 22 nuclear reactors. In addition, our International operations also provide turn-key services and sub-contract services for the treatment, processing, storage and disposal of radioactive waste from nuclear sites and non-nuclear facilities such as hospitals, research facilities and other manufacturing and industrial facilities. The Global Commercial Group reports its results under three separate operating business divisions: Commercial Services ("CS"), Logistics, Processing and Disposal ("LP&D") and International. Exelon Transaction On December 11, 2007, we, through our subsidiary ZionSolutions, LLC ("ZionSolutions"), entered into certain agreements with Exelon Generation Company LLC ("Exelon"), (the "Exelon Agreements") to dismantle Exelon's Zion nuclear facility located in Zion, Illinois ("Zion Station"), which ceased operation in 1998. The transaction closed on September 1, 2010. Upon closing, Exelon transferred to ZionSolutions substantially all of the assets (other than land) associated with Zion Station, including assets held in nuclear decommissioning trusts. In consideration for Exelon's transfer of those assets, ZionSolutions agreed to assume decommissioning and other liabilities associated with Zion Station. ZionSolutions also took possession and control of the land associated with Zion Station pursuant to a lease agreement executed at the closing. ZionSolutions is under contract to complete the required decommissioning work according to an established schedule and to construct a dry cask storage facility on the land for spent nuclear fuel currently held in spent fuel pools at Zion Station. Exelon retains ownership of the land and the spent nuclear fuel and associated operational responsibilities following completion of the Zion Station D&D project. The Nuclear Regulatory Commission ("NRC") approved the transfer of the facility operating licenses and conforming license amendments from Exelon to ZionSolutions ("License Transfer"). To satisfy the conditions of the NRC order approving the License Transfer, we (i) secured a $200.0 million letter of credit facility, (ii) granted an irrevocable easement of disposal capacity of 7.5 million cubic feet at our Clive disposal facility, and (iii) purchased the insurance required of a licensee under the NRC's regulations. We provided a guarantee as primary obligor to the full and prompt payment and performance by ZionSolutions of all its obligations under the various agreements with Exelon. This guarantee would deplete Company assets before the $200.0 million letter of credit (described below) would fund remaining D&D activities. We also pledged 100% of our interests in ZionSolutions to Exelon. In addition, we were required to obtain a $200.0 million letter of credit facility to further support the D&D activities at the Zion Station, which is held in a backup trust. If the Company exhausts its resources and ability to complete the D&D activities and in the event of a material default (as defined within the Credit Support Agreement), Exelon may exercise its rights to take possession of ZionSolutions. At that point, through their ownership of ZionSolutions, Exelon (not the Company) would then be entitled to control the funds associated with the letter of credit through control of the backup trust. Under the terms of the Company's financing arrangements the Company obtained restricted cash and took on a liability for the letter of credit facility. *Accounting for the Exelon Transaction* As discussed above, in December 2007, we entered into certain agreements with Exelon to dismantle the Zion Station, including a planning contract under which we were engaged to perform certain preparatory services, with payment contingent upon closing of an asset sale agreement. Although we entered into this contract in December 2007, we postponed the closing of the transaction due to the financial crisis affecting the stock markets at the time, and as a result all costs associated with the execution of the planning phase were also deferred. The transaction closed on September 1, 2010. After closing, we recognized the costs and the related revenue associated with the planning contract in our consolidated statements of operations and comprehensive income (loss), with $5.1 million in revenue representing the related gross profit being deferred over the period of D&D work. On the date of the closing of the asset sale agreement, the trust fund investments of approximately $801.4 million previously held by Exelon for the purpose of decommissioning the Zion Station nuclear power plant were transferred to us and the use of those funds, and any investment returns arising therein, remains restricted solely to that purpose. The investments are classified as trading securities and as such, the investment gains and losses are recorded in the statements of operations and comprehensive income (loss) as other income (expense), net. As part of this transaction, we have assumed Exelon's cost basis in the investments, for tax purposes, which included an unrealized gain of approximately $171.7 million at the closing date which resulted in a deferred tax liability of approximately $34.3 million. To the extent that the trust fund assets exceed the costs to perform the D&D work, we have a contractual obligation to return any excess funds to Exelon. Throughout the period over which we perform the D&D work, we will assess whether such a contingent liability exists using the measurement thresholds under ASC 450-20. As the trust fund assets that were transferred to us represent a prepayment of fees to perform the D&D work, we also recorded deferred revenue, including deferred revenue associated with the planning contract, of $772.2 million. Revenue recognition throughout the life of the project is based on the proportional performance method using a cost-to-cost approach. In conjunction with the acquisition of the shut down nuclear power plant, we became responsible for and assumed the asset retirement obligations ("AROs") for the plant and we established and initially measured an ARO in accordance with ASC 410-20. Subsequent measurement of the ARO follows ASC 410-20 accounting guidance, including the recognition of accretion expense, reassessment of the remaining liability using our estimated costs to complete the D&D work plus a profit margin and recognition of the ARO gain as the obligation is settled. The ARO gain results from the requirement to record costs plus an estimate of third-party profit in determining the ARO. When we perform the work using internal resources and reduce the ARO for work performed we recognize a gain if actual costs are less than the estimated costs plus the third-party profit. Accretion expense and the ARO gain are recorded within cost of revenue because, through this arrangement, we are providing D&D services to a customer. Any change to the ARO as a result of cost estimate changes are also recorded to cost of revenue in the statements of operations and comprehensive income (loss) in the period identified. We also recorded deferred costs to reflect the costs incurred to acquire the future revenue stream. The deferred cost balance was initially recorded at $767.1 million, which is the same value as the initial ARO, and is amortized into cost of revenue in the same manner as deferred revenue, using the proportional performance method.

(1) Description of Business

Envirocare of Utah, Inc. (predecessor) was formed in 1988 to operate a disposal facility for mixed waste, uranium mill tailings and Class A low-level radioactive waste ("LLRW") in Clive, Utah. In January 2005, the predecessor converted to a limited liability company, Envirocare of Utah, LLC ("Envirocare"). Immediately thereafter, the sole member of Envirocare sold all of its member interest to ENV Holdings LLC ("ENV Holdings"). In 2006, we changed our name from Envirocare of Utah, LLC to EnergySolutions, LLC ("we," "our," "EnergySolutions" or the "Company"). Since 2005, we have expanded and diversified our operations through a series of strategic acquisitions, including the decontamination and decommissioning ("D&D") division of Scientech, LLC ("Scientech") in October 2005, BNG America, LLC ("BNGA") in February 2006, Duratek, Inc. ("Duratek") in June 2006, Safeguard International Solutions, Ltd. (renamed ESEU Services Limited ("ESEU")) in December 2006, Parallax, Inc. (renamed EnergySolutions Performance Strategies) in January 2007, Reactor Sites Management Company Limited ("RSMC") in June 2007, NUKEM Corporation (renamed EnergySolutions Diversified Services, Inc.) in July 2007, and Monserco Limited ("Monserco") in December 2007.

On November 20, 2007, the date of the completion of our initial public offering, we completed our conversion to a corporate structure whereby EnergySolutions, LLC became a wholly owned subsidiary of EnergySolutions, Inc. As a result, the member of EnergySolutions, LLC contributed its membership equity interest for 75.2 million shares of $0.01 par value common stock of EnergySolutions, Inc. EnergySolutions, Inc., is organized and existing under the General Corporation Law of the state of Delaware.

On July 30, 2008, we completed a secondary public offering of 35 million shares of common stock offered by ENV Holdings, as selling stockholder. The underwriters of the offering subsequently exercised their over-allotment option and purchased 5.25 million additional shares of our common stock from ENV Holdings. Following completion of these transactions, ENV Holdings owned approximately 16.7% of our outstanding shares of common stock. We did not receive any proceeds from the sale of shares by ENV Holdings and recognized expenses of $1.8 million for the year ended December 31, 2008. On February 13, 2009, ENV Holdings completed a distribution of all of our shares to its members on a pro rata basis for no consideration. As a result, ENV Holdings is no longer the beneficial owner, directly or indirectly, of any shares of our common stock.

On January 7, 2013, we entered into an Agreement and Plan of Merger (the "Merger Agreement") with Rockwell Holdco, Inc., a Delaware corporation ("Parent"), and Rockwell Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger Sub"). Parent and Merger Sub are affiliates of Energy Capital Partners II, LP and its parallel funds (together with its affiliates, "Energy Capital Partners"), a leading private equity firm focused on investing in North America's energy infrastructure. Pursuant to the Merger Agreement, the Merger Sub will merge with and into the Company (the "Merger") and we will become a wholly-owned subsidiary of Parent. The Merger will only be able to be consummated after the stockholders of the Company have adopted the Merger Agreement at a meeting of stockholders and following the satisfaction or waiver of a number of conditions set forth in the Merger Agreement. Upon completion of the Merger, each outstanding share of the Company's common stock other than shares of common stock held in the treasury of the Company or owned by Parent, any affiliates of Parent, Merger Sub, a subsidiary of the Company or by stockholders who have validly exercised their appraisal rights under Delaware law, will be converted into the right to receive cash in an amount equal to $3.75, without interest and subject to any required withholding of taxes.

The obligation of Parent and Merger Sub to consummate the Merger is subject to the satisfaction or waiver of a number of conditions set forth in the Merger Agreement, including (i) the adoption of the Merger Agreement and approval of the transactions contemplated thereby by stockholders of the Company owning at least a majority of outstanding shares of the Company's common stock, (ii) the expiration or termination of any applicable waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act"), (iii) a notification from the Committee on Foreign Investment in the United States ("CFIUS") that it has determined not to investigate the transactions contemplated in the Merger Agreement, but only if the Company and Parent have elected to make a filing to CFIUS, (iv) the absence of any law or order preventing the consummation of the Merger, (v) the obtaining of certain regulatory approvals, including approval from the NRC and consent from the NDA, (vi) subject to certain exceptions, the accuracy of the Company's representations and warranties, (vii) the Company's compliance in all material respect with its obligations under the Merger Agreement and (viii) the absence of a material adverse effect on the Company.

The early termination of the waiting period under the HSR Act was granted and became effective on February 1, 2013. The Company submitted the formal consent application to the NDA on January 21, 2013. The NDA, in a letter dated January 24, 2013, gave its consent to the change in control of EnergySolutions EU Limited in satisfaction of this aspect of the Merger Agreement. Also, the Company and Parent determined not to make a filing with CFIUS pursuant to the Defense Protection Act of 1950, based on their belief that no such filing is necessary with respect to the transactions contemplated by the Merger Agreement.

We report our results through two major operating groups: the Government Group and the Global Commercial Group. The Government Group derives its revenue from United States ("U.S.") government customers for the management and operation or clean-up of facilities with radioactive materials. Our U.S. government customers are primarily individual offices, departments and administrations within the U.S. Department of Energy ("DOE") and U.S. Department of Defense ("DOD"). The Global Commercial Group provides a broad range of services both nationally and internationally, including (i) on-site D&D services to commercial customers such as power and utility companies, pharmaceutical companies, research laboratories, universities, industrial facilities, state agencies and other commercial entities that are involved with nuclear materials; (ii) logistics, transportation, processing and disposal services to both government and commercial customers at our facility in Clive, Utah, our four facilities in Tennessee, or our two facilities in Barnwell, South Carolina; and (iii) comprehensive long-term stewardship D&D work for shut-down nuclear power plants and similar operations. Our international operations derive revenue primarily through contracts with the Nuclear Decommissioning Authority ("NDA") in the United Kingdom ("U.K.") to operate, manage and decommission ten Magnox sites with 22 nuclear reactors. In addition, our International operations also provide turn-key services and sub-contract services for the treatment, processing, storage and disposal of radioactive waste from nuclear sites and non-nuclear facilities such as hospitals, research facilities and other manufacturing and industrial facilities. The Global Commercial Group reports its results under three separate operating business divisions: Commercial Services ("CS"), Logistics, Processing and Disposal ("LP&D") and International.

Exelon Transaction

On December 11, 2007, we, through our subsidiary ZionSolutions, LLC ("ZionSolutions"), entered into certain agreements with Exelon Generation Company LLC ("Exelon"), (the "Exelon Agreements") to dismantle Exelon's Zion nuclear facility located in Zion, Illinois ("Zion Station"), which ceased operation in 1998. The transaction closed on September 1, 2010. Upon closing, Exelon transferred to ZionSolutions substantially all of the assets (other than land) associated with Zion Station, including assets held in nuclear decommissioning trusts. In consideration for Exelon's transfer of those assets, ZionSolutions agreed to assume decommissioning and other liabilities associated with Zion Station. ZionSolutions also took possession and control of the land associated with Zion Station pursuant to a lease agreement executed at the closing. ZionSolutions is under contract to complete the required decommissioning work according to an established schedule and to construct a dry cask storage facility on the land for spent nuclear fuel currently held in spent fuel pools at Zion Station. Exelon retains ownership of the land and the spent nuclear fuel and associated operational responsibilities following completion of the Zion Station D&D project. The Nuclear Regulatory Commission ("NRC") approved the transfer of the facility operating licenses and conforming license amendments from Exelon to ZionSolutions ("License Transfer").

To satisfy the conditions of the NRC order approving the License Transfer, we (i) secured a $200.0 million letter of credit facility, (ii) granted an irrevocable easement of disposal capacity of 7.5 million cubic feet at our Clive disposal facility, and (iii) purchased the insurance required of a licensee under the NRC's regulations.

We provided a guarantee as primary obligor to the full and prompt payment and performance by ZionSolutions of all its obligations under the various agreements with Exelon. This guarantee would deplete Company assets before the $200.0 million letter of credit (described below) would fund remaining D&D activities. We also pledged 100% of our interests in ZionSolutions to Exelon. In addition, we were required to obtain a $200.0 million letter of credit facility to further support the D&D activities at the Zion Station, which is held in a backup trust. If the Company exhausts its resources and ability to complete the D&D activities and in the event of a material default (as defined within the Credit Support Agreement), Exelon may exercise its rights to take possession of ZionSolutions. At that point, through their ownership of ZionSolutions, Exelon (not the Company) would then be entitled to control the funds associated with the letter of credit through control of the backup trust. Under the terms of the Company's financing arrangements the Company obtained restricted cash and took on a liability for the letter of credit facility.

Accounting for the Exelon Transaction

As discussed above, in December 2007, we entered into certain agreements with Exelon to dismantle the Zion Station, including a planning contract under which we were engaged to perform certain preparatory services, with payment contingent upon closing of an asset sale agreement. Although we entered into this contract in December 2007, we postponed the closing of the transaction due to the financial crisis affecting the stock markets at the time, and as a result all costs associated with the execution of the planning phase were also deferred. The transaction closed on September 1, 2010. After closing, we recognized the costs and the related revenue associated with the planning contract in our consolidated statements of operations and comprehensive income (loss), with $5.1 million in revenue representing the related gross profit being deferred over the period of D&D work.

On the date of the closing of the asset sale agreement, the trust fund investments of approximately $801.4 million previously held by Exelon for the purpose of decommissioning the Zion Station nuclear power plant were transferred to us and the use of those funds, and any investment returns arising therein, remains restricted solely to that purpose. The investments are classified as trading securities and as such, the investment gains and losses are recorded in the statements of operations and comprehensive income (loss) as other income (expense), net. As part of this transaction, we have assumed Exelon's cost basis in the investments, for tax purposes, which included an unrealized gain of approximately $171.7 million at the closing date which resulted in a deferred tax liability of approximately $34.3 million. To the extent that the trust fund assets exceed the costs to perform the D&D work, we have a contractual obligation to return any excess funds to Exelon. Throughout the period over which we perform the D&D work, we will assess whether such a contingent liability exists using the measurement thresholds under ASC 450-20.

As the trust fund assets that were transferred to us represent a prepayment of fees to perform the D&D work, we also recorded deferred revenue, including deferred revenue associated with the planning contract, of $772.2 million. Revenue recognition throughout the life of the project is based on the proportional performance method using a cost-to-cost approach.

In conjunction with the acquisition of the shut down nuclear power plant, we became responsible for and assumed the asset retirement obligations ("AROs") for the plant and we established and initially measured an ARO in accordance with ASC 410-20. Subsequent measurement of the ARO follows ASC 410-20 accounting guidance, including the recognition of accretion expense, reassessment of the remaining liability using our estimated costs to complete the D&D work plus a profit margin and recognition of the ARO gain as the obligation is settled. The ARO gain results from the requirement to record costs plus an estimate of third-party profit in determining the ARO. When we perform the work using internal resources and reduce the ARO for work performed we recognize a gain if actual costs are less than the estimated costs plus the third-party profit. Accretion expense and the ARO gain are recorded within cost of revenue because, through this arrangement, we are providing D&D services to a customer. Any change to the ARO as a result of cost estimate changes are also recorded to cost of revenue in the statements of operations and comprehensive income (loss) in the period identified. We also recorded deferred costs to reflect the costs incurred to acquire the future revenue stream. The deferred cost balance was initially recorded at $767.1 million, which is the same value as the initial ARO, and is amortized into cost of revenue in the same manner as deferred revenue, using the proportional performance method.