Summary of Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2013
Accounting Policies [Abstract]
Principles of Consolidation	The consolidated financial statements include the accounts of CDI Corp. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated.
Basis of Presentation	The accompanying unaudited consolidated financial statements include all adjustments (consisting only of normal, recurring adjustments) necessary for a fair presentation of financial position, results of operations and cash flows in conformity with generally accepted accounting principles in the United States of America (“GAAP”), the instructions to Form 10-Q and Article 10 of Regulation S-X of the United States Securities and Exchange Commission (“SEC”) for interim financial reporting. These statements should be read in conjunction with the Company's Form 10-K filed with the SEC on March 1, 2013. Results for the three months ended March 31, 2013 are not necessarily indicative of results that may be expected for the full year.
Use of Estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts disclosed in the financial statements and accompanying notes. Estimates, by their nature, are based on judgment and available information. Actual results could differ materially from those estimates. Significant estimates inherent in the preparation of the accompanying consolidated financial statements include the assumptions used in the determination of the allowance for doubtful accounts receivable, impairment assessment of goodwill, determination of the recoverability of long-lived assets, assessment of legal contingencies and calculation of income taxes.

Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2013

The consolidated financial statements include the accounts of CDI Corp. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated.

Basis of Presentation

The accompanying unaudited consolidated financial statements include all adjustments (consisting only of normal, recurring adjustments) necessary for a fair presentation of financial position, results of operations and cash flows in conformity with generally accepted accounting principles in the United States of America (“GAAP”), the instructions to Form 10-Q and Article 10 of Regulation S-X of the United States Securities and Exchange Commission (“SEC”) for interim financial reporting. These statements should be read in conjunction with the Company's Form 10-K filed with the SEC on March 1, 2013. Results for the three months ended March 31, 2013 are not necessarily indicative of results that may be expected for the full year.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts disclosed in the financial statements and accompanying notes. Estimates, by their nature, are based on judgment and available information. Actual results could differ materially from those estimates.

Significant estimates inherent in the preparation of the accompanying consolidated financial statements include the assumptions used in the determination of the allowance for doubtful accounts receivable, impairment assessment of goodwill, determination of the recoverability of long-lived assets, assessment of legal contingencies and calculation of income taxes.

- 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

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+ Details

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

+ References+ Details