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Description Of Business And Summary Of Significant Accounting Policies (Policies) | 9 Months Ended
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Sep. 30, 2014
Description of Business and Summary of Significant Accounting Policies [Abstract] |
Basis of Presentation, Policy | Basis of Presentation The accompanying unaudited interim consolidated financial statements as of September 30, 2014 and for the three and nine months ended September 30, 2014 and 2013 (the "consolidated financial statements") have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (the "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, 2013 (the "December 31, 2013 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, 2013 financial statements. 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") was previously owned directly by CDW Holdings LLC ("CDW Holdings"), a company controlled by investment funds affiliated with Madison Dearborn Partners, LLC ("Madison Dearborn") and Providence Equity Partners, L.L.C. ("Providence Equity," and together with Madison Dearborn, the "Sponsors"), certain other co-investors and certain members of CDW management. On July 2, 2013, Parent completed an initial public offering (the "IPO") of its common stock. In connection with the IPO, CDW Holdings distributed all of its shares of Parent's common stock to its members in June 2013 in accordance with the members' respective membership interests and was subsequently dissolved in August 2013. See Note 6 for additional discussion of the IPO. 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 of the Company. 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 12 and does not hold any material assets or engage in any business activities or operations. Throughout these notes, the terms the “Company” and “CDW” refer to Parent and its 100% owned subsidiaries.
Principles of Consolidation, Policy | 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, Policy | 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, 2013 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 nine months ended September 30, 2014.

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- Definition Disclosure of accounting policy for basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS). + References No definition available. + Details
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- Definition Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=18733093&loc=d3e5614-111684 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.3A-02) -URI http://asc.fasb.org/extlink&oid=27015204&loc=d3e355033-122828 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph k -Article 1 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02, 03 -Article 3A + Details
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- Definition Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6143-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6132-108592 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6061-108592 + Details
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