Description Of Business And Summary Of Significant Accounting Policies	3 Months Ended
Mar. 31, 2013
Description of Business and Summary of Significant Accounting Policies [Abstract]
Description Of Business And Summary Of Significant Accounting Policies	Description of Business and Summary of Significant Accounting Policies Description of Business CDW is a Fortune 500 company and a leading provider of integrated information technology (“IT”) solutions to small, medium and large business, government, education and healthcare customers in the U.S. and Canada. The Company's offerings range from discrete hardware and software products to integrated IT solutions such as mobility, security, data center optimization, cloud computing, virtualization and collaboration. Basis of Presentation The accompanying unaudited interim consolidated financial statements as of March 31, 2013 and for the three months ended March 31, 2013 and 2012 ("consolidated financial statements") have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission ("SEC") for interim financial statements. Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") have been condensed or omitted pursuant to such rules and regulations. The consolidated financial statements should be read in conjunction with the audited consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2012 ("December 31, 2012 financial statements"). The significant accounting policies used in preparing these consolidated financial statements were applied on a basis consistent with those reflected in the December 31, 2012 financial statements, except as disclosed in Note 2. In the opinion of management, the consolidated financial statements contain all adjustments (consisting of a normal, recurring nature) necessary to present fairly the Company's financial position, results of operations, comprehensive income, cash flows and changes in shareholders' equity as of the dates and for the periods indicated. The unaudited consolidated statements of operations for such interim periods reported are not necessarily indicative of results for the full year. CDW Corporation ("Parent") is owned directly by CDW Holdings LLC, a company controlled by investment funds affiliated with Madison Dearborn Partners, LLC and Providence Equity Partners, L.L.C., certain other co-investors and certain members of CDW management. Parent has two 100% owned subsidiaries, CDW LLC and CDW Finance Corporation. CDW LLC is an Illinois limited liability company that, together with its 100% owned subsidiaries, holds all material assets and conducts all business activities and operations. CDW Finance Corporation is a Delaware corporation formed for the sole purpose of acting as co-issuer of certain debt obligations as described in Note 10 and does not hold any material assets or engage in any business activities or operations. Throughout this report, the terms “the Company” and “CDW” refer to Parent and its 100% owned subsidiaries. Principles of Consolidation The accompanying consolidated financial statements include the accounts of Parent and its 100% owned subsidiaries. All intercompany transactions and accounts are eliminated in consolidation. Use of Estimates The preparation of consolidated financial statements in accordance with GAAP requires management to make use of certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reported periods. The Company bases its estimates on historical experience and on various other assumptions that management believes are reasonable under the circumstances, the results of which form the basis for making judgments about carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates. The notes to the consolidated financial statements contained in the December 31, 2012 financial statements include an additional discussion of the significant accounting policies and estimates used in the preparation of the Company's consolidated financial statements. There have been no material changes to the Company's significant accounting policies and estimates during the three months ended March 31, 2013. Reclassifications Certain reclassifications have been made to the prior period consolidated financial statements to conform to the current period presentation. Registration Statement on Form S-1 On March 22, 2013, the Company filed a Registration Statement on Form S-1 with the SEC relating to the proposed initial public offering of its common shares. The number of shares to be offered and the price range for the offering have not yet been determined. The Company makes no assurances that the Registration Statement on Form S-1 will be declared effective or that the proposed transaction will be consummated.

Description of Business and Summary of Significant Accounting Policies

Description of Business

CDW is a Fortune 500 company and a leading provider of integrated information technology (“IT”) solutions to small, medium and large business, government, education and healthcare customers in the U.S. and Canada. The Company's offerings range from discrete hardware and software products to integrated IT solutions such as mobility, security, data center optimization, cloud computing, virtualization and collaboration.

Basis of Presentation

The accompanying unaudited interim consolidated financial statements as of March 31, 2013 and for the three months ended March 31, 2013 and 2012 ("consolidated financial statements") have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission ("SEC") for interim financial statements. Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") have been condensed or omitted pursuant to such rules and regulations. The consolidated financial statements should be read in conjunction with the audited consolidated financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2012 ("December 31, 2012 financial statements"). The significant accounting policies used in preparing these consolidated financial statements were applied on a basis consistent with those reflected in the December 31, 2012 financial statements, except as disclosed in Note 2. In the opinion of management, the consolidated financial statements contain all adjustments (consisting of a normal, recurring nature) necessary to present fairly the Company's financial position, results of operations, comprehensive income, cash flows and changes in shareholders' equity as of the dates and for the periods indicated. The unaudited consolidated statements of operations for such interim periods reported are not necessarily indicative of results for the full year.

CDW Corporation ("Parent") is owned directly by CDW Holdings LLC, a company controlled by investment funds affiliated with Madison Dearborn Partners, LLC and Providence Equity Partners, L.L.C., certain other co-investors and certain members of CDW management.

Parent has two 100% owned subsidiaries, CDW LLC and CDW Finance Corporation. CDW LLC is an Illinois limited liability company that, together with its 100% owned subsidiaries, holds all material assets and conducts all business activities and operations. CDW Finance Corporation is a Delaware corporation formed for the sole purpose of acting as co-issuer of certain debt obligations as described in Note 10 and does not hold any material assets or engage in any business activities or operations.

Throughout this report, the terms “the Company” and “CDW” refer to Parent and its 100% owned subsidiaries.

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of Parent and its 100% owned subsidiaries. All intercompany transactions and accounts are eliminated in consolidation.

Use of Estimates

The preparation of consolidated financial statements in accordance with GAAP requires management to make use of certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reported periods. The Company bases its estimates on historical experience and on various other assumptions that management believes are reasonable under the circumstances, the results of which form the basis for making judgments about carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates.

The notes to the consolidated financial statements contained in the December 31, 2012 financial statements include an additional discussion of the significant accounting policies and estimates used in the preparation of the Company's consolidated financial statements. There have been no material changes to the Company's significant accounting policies and estimates during the three months ended March 31, 2013.

Reclassifications

Certain reclassifications have been made to the prior period consolidated financial statements to conform to the current period presentation.

Registration Statement on Form S-1

On March 22, 2013, the Company filed a Registration Statement on Form S-1 with the SEC relating to the proposed initial public offering of its common shares. The number of shares to be offered and the price range for the offering have not yet been determined. The Company makes no assurances that the Registration Statement on Form S-1 will be declared effective or that the proposed transaction will be consummated.