Summary of Significant Accounting Policies UseofEstimates (Policies)	6 Months Ended
Jun. 30, 2012
Summary of Significant Accounting Policies [Abstract]
Consolidation, Policy [Policy Text Block]	Principles of Consolidation The accompanying unaudited consolidated financial statements include the accounts of CDI Corp. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated.
Use of Estimates, Policy [Policy Text Block]	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 unaudited consolidated financial statements include valuation of accounts receivable, goodwill, intangible assets, other long-lived assets, legal contingencies and assumptions used in the calculations of income taxes.
Reclassification, Policy [Policy Text Block]	Reclassifications Certain historical financial information in the prior period consolidated financial statements has been reclassified to conform to the current period presentation. Historical segment financial information has been reclassified as a result of the organizational changes announced in December 2011 to reflect the realignment of the Company's reporting segments and centralization of certain support functions previously contained in the reporting segments. (See Note 11-Reporting Segments, in the notes to the consolidated financial statements included in this Form 10-Q Report).
Basis of Accounting, Policy [Policy Text Block]	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 6, 2012. Results for the six months ended June 30, 2012 are not necessarily indicative of results that may be expected for the full year.

Summary of Significant Accounting Policies UseofEstimates (Policies)

6 Months Ended

Jun. 30, 2012

Summary of Significant Accounting Policies [Abstract]

Consolidation, Policy [Policy Text Block]

Principles of Consolidation

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

Use of Estimates, Policy [Policy Text Block]

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 unaudited consolidated financial statements include valuation of accounts receivable, goodwill, intangible assets, other long-lived assets, legal contingencies and assumptions used in the calculations of income taxes.

Reclassification, Policy [Policy Text Block]

Reclassifications

Certain historical financial information in the prior period consolidated financial statements has been reclassified to conform to the current period presentation. Historical segment financial information has been reclassified as a result of the organizational changes announced in December 2011 to reflect the realignment of the Company's reporting segments and centralization of certain support functions previously contained in the reporting segments. (See Note 11-Reporting Segments, in the notes to the consolidated financial statements included in this Form 10-Q Report).

Basis of Accounting, Policy [Policy Text Block]

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 6, 2012. Results for the six months ended June 30, 2012 are not necessarily indicative of results that may be expected for the full year.

- 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