Nature of Business and Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2011
Nature of Business and Summary of Significant Accounting Policies [Abstract]
NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	NOTE 1 — NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations Allis-Chalmers Energy Inc. and subsidiaries (“Allis-Chalmers”, “we”, “our” or “us”) is a multi-faceted oilfield service company that provides services and equipment to oil and natural gas exploration and production companies throughout the United States including Texas, Louisiana, Pennsylvania, Arkansas, West Virginia, Oklahoma, Colorado, offshore in the Gulf of Mexico, and internationally, primarily in Argentina, Brazil, Bolivia and Mexico. We operate in two sectors of the oil and natural gas service industry: Well Services and Drilling Services. We derive operating revenues from rates per day and rates per job that we charge for the labor and equipment required to provide a service and rates per day for equipment and tools that we rent to our customers. The price we charge for our services depends upon several factors, including the level of oil and natural gas drilling activity and the competitive environment in the particular geographic regions in which we operate. Contracts are awarded based on price, quality of service and equipment and general reputation and experience of our personnel. The principal operating costs are direct and indirect labor and benefits, repairs and maintenance of our equipment, insurance, equipment rentals, fuel, depreciation and general and administrative expenses. Basis of Presentation On February 23, 2011, Allis-Chalmers Energy Inc., a Delaware corporation, completed its merger (the “Merger”) with and into Wellco Sub Company (“Wellco”), a Delaware corporation and wholly owned subsidiary of Seawell Limited (“Seawell”), with Wellco continuing as the surviving entity under the name Allis-Chalmers Energy Inc. The Merger was effected pursuant to the Agreement and Plan of Merger, dated as of August 10, 2010, by and among Allis-Chalmers, Seawell and Wellco, as amended by the Amendment Agreement, dated as of October 10, 2010, by and among Allis-Chalmers, Seawell and Wellco (as so amended, the “Merger Agreement”). Following the Merger, Seawell began operating under the name Archer Limited (“Archer” or “Parent”). As of the Merger date, our assets and liabilities have been adjusted to their fair values (see Note 2) based on the purchase price resulting in changes to depreciation, amortization and interest in the successor period; therefore, the financial information for the period subsequent to the Merger is not fully comparable. The financial statements and accompanying footnotes have been separated with a black line to present pre-merger activity as the “Predecessor” company and post-merger activity as the “Successor” company. “Predecessor” refers to the operations of Allis-Chalmers prior to the consummation of the Merger and “Successor” refers to the operations of Allis-Chalmers subsequent to the Merger. The Merger date for accounting purposes has been designated as March 1, 2011. Our unaudited consolidated condensed financial statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission, or SEC. Accordingly, certain information and disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles have been condensed or omitted. We believe that the presentations and disclosures herein are adequate to make the information not misleading. The unaudited consolidated condensed financial statements reflect all adjustments (consisting of normal recurring adjustments) necessary for a fair statement of the interim periods. These unaudited consolidated condensed financial statements should be read in conjunction with our restated audited consolidated financial statements included in Amendment No. 1 to our Annual Report on Form 10-K for the year ended December 31, 2010 filed with the SEC on September 1, 2011 (the “Form 10-K/A”). The results of operations for the interim periods are not necessarily indicative of the results of operations to be expected for the full year. The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Future events and their effects cannot be perceived with certainty. Accordingly, our accounting estimates require the exercise of judgment. While management believes that the estimates and assumptions used in the preparation of the consolidated financial statements are appropriate, actual results could differ from those estimates. Estimates are used for, but are not limited to, determining the following: allowance for doubtful accounts; recoverability of long-lived assets and intangibles; useful lives used in depreciation and amortization; stock-based compensation; income taxes and valuation allowances. The accounting estimates used in the preparation of the consolidated financial statements may change as new events occur, as more experience is acquired, as additional information is obtained or as our operating environment changes. Financial Instruments Financial instruments consist of cash and cash equivalents, restricted cash, accounts receivable and payable, and debt. The carrying value of cash and cash equivalents, restricted cash and accounts receivable and payable approximate fair value due to their short-term nature. Restricted cash relates to deposits at a financial institution to secure $3.8 million of outstanding letters of credit. We believe the fair values and the carrying value of our debt, excluding the senior notes, would not be materially different due to the instruments’ interest rates approximating market rates for similar borrowings at June 30, 2011. Our senior notes, in the approximate aggregate amount of $446.6 million, trade “over the counter” in limited amounts and on an infrequent basis. In connection with the Merger, the recorded fair value of our senior notes was increased by $19.3 million based on the traded value at Merger date. The price at which our senior notes trade is based on many factors such as the level of interest rates, the economic environment, the outlook for the oilfield services industry and the perceived credit risk. Recent Accounting Pronouncements We consider all newly issued but not yet adopted accounting pronouncements applicable to our operations and the preparation of our consolidated condensed financial statements. We do not believe that any issued accounting pronouncements not yet adopted by us will have a material impact on our consolidated condensed financial statements.

NOTE 1 — NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Nature of Operations

Allis-Chalmers Energy Inc. and subsidiaries (“Allis-Chalmers”, “we”, “our” or “us”) is a multi-faceted oilfield service company that provides services and equipment to oil and natural gas exploration and production companies throughout the United States including Texas, Louisiana, Pennsylvania, Arkansas, West Virginia, Oklahoma, Colorado, offshore in the Gulf of Mexico, and internationally, primarily in Argentina, Brazil, Bolivia and Mexico. We operate in two sectors of the oil and natural gas service industry: Well Services and Drilling Services.

We derive operating revenues from rates per day and rates per job that we charge for the labor and equipment required to provide a service and rates per day for equipment and tools that we rent to our customers. The price we charge for our services depends upon several factors, including the level of oil and natural gas drilling activity and the competitive environment in the particular geographic regions in which we operate. Contracts are awarded based on price, quality of service and equipment and general reputation and experience of our personnel. The principal operating costs are direct and indirect labor and benefits, repairs and maintenance of our equipment, insurance, equipment rentals, fuel, depreciation and general and administrative expenses.

Basis of Presentation

On February 23, 2011, Allis-Chalmers Energy Inc., a Delaware corporation, completed its merger (the “Merger”) with and into Wellco Sub Company (“Wellco”), a Delaware corporation and wholly owned subsidiary of Seawell Limited (“Seawell”), with Wellco continuing as the surviving entity under the name Allis-Chalmers Energy Inc. The Merger was effected pursuant to the Agreement and Plan of Merger, dated as of August 10, 2010, by and among Allis-Chalmers, Seawell and Wellco, as amended by the Amendment Agreement, dated as of October 10, 2010, by and among Allis-Chalmers, Seawell and Wellco (as so amended, the “Merger Agreement”). Following the Merger, Seawell began operating under the name Archer Limited (“Archer” or “Parent”). As of the Merger date, our assets and liabilities have been adjusted to their fair values (see Note 2) based on the purchase price resulting in changes to depreciation, amortization and interest in the successor period; therefore, the financial information for the period subsequent to the Merger is not fully comparable. The financial statements and accompanying footnotes have been separated with a black line to present pre-merger activity as the “Predecessor” company and post-merger activity as the “Successor” company. “Predecessor” refers to the operations of Allis-Chalmers prior to the consummation of the Merger and “Successor” refers to the operations of Allis-Chalmers subsequent to the Merger. The Merger date for accounting purposes has been designated as March 1, 2011.

Our unaudited consolidated condensed financial statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission, or SEC. Accordingly, certain information and disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles have been condensed or omitted. We believe that the presentations and disclosures herein are adequate to make the information not misleading. The unaudited consolidated condensed financial statements reflect all adjustments (consisting of normal recurring adjustments) necessary for a fair statement of the interim periods. These unaudited consolidated condensed financial statements should be read in conjunction with our restated audited consolidated financial statements included in Amendment No. 1 to our Annual Report on Form 10-K for the year ended December 31, 2010 filed with the SEC on September 1, 2011 (the “Form 10-K/A”). The results of operations for the interim periods are not necessarily indicative of the results of operations to be expected for the full year.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Future events and their effects cannot be perceived with certainty. Accordingly, our accounting estimates require the exercise of judgment. While management believes that the estimates and assumptions used in the preparation of the consolidated financial statements are appropriate, actual results could differ from those estimates. Estimates are used for, but are not limited to, determining the following: allowance for doubtful accounts; recoverability of long-lived assets and intangibles; useful lives used in depreciation and amortization; stock-based compensation; income taxes and valuation allowances. The accounting estimates used in the preparation of the consolidated financial statements may change as new events occur, as more experience is acquired, as additional information is obtained or as our operating environment changes.

Financial Instruments

Financial instruments consist of cash and cash equivalents, restricted cash, accounts receivable and payable, and debt. The carrying value of cash and cash equivalents, restricted cash and accounts receivable and payable approximate fair value due to their short-term nature. Restricted cash relates to deposits at a financial institution to secure $3.8 million of outstanding letters of credit. We believe the fair values and the carrying value of our debt, excluding the senior notes, would not be materially different due to the instruments’ interest rates approximating market rates for similar borrowings at June 30, 2011. Our senior notes, in the approximate aggregate amount of $446.6 million, trade “over the counter” in limited amounts and on an infrequent basis. In connection with the Merger, the recorded fair value of our senior notes was increased by $19.3 million based on the traded value at Merger date. The price at which our senior notes trade is based on many factors such as the level of interest rates, the economic environment, the outlook for the oilfield services industry and the perceived credit risk.

Recent Accounting Pronouncements

We consider all newly issued but not yet adopted accounting pronouncements applicable to our operations and the preparation of our consolidated condensed financial statements. We do not believe that any issued accounting pronouncements not yet adopted by us will have a material impact on our consolidated condensed financial statements.