Capital Structure	12 Months Ended
Capital Structure	Dec. 31, 2012
Capital Structure [Abstract]
Stockholders' Equity Note Disclosure [Text Block]	Capital Structure The Company has two classes of common stock: Class A and Class B. Class A Common Stock Holders of the Company's Class A common stock are entitled to one vote for each share held of record on all matters submitted to a vote of stockholders. Holders of the Company's Class A common stock are entitled to receive dividends when and if declared by the Company's board of directors out of funds legally available, subject to any statutory or contractual restrictions on the payment of dividends and to any restrictions on the payment of dividends imposed by the terms of any outstanding preferred stock. In the event of the Company's merger or consolidation with or into another entity in connection with which shares of the Company's Class A common stock are converted into or exchangeable for shares of stock, other securities or property (including cash), all holders of shares of the Company's Class A common stock will thereafter be entitled to receive the same kind and amount of shares of stock and other securities and property (including cash). Upon the Company's dissolution or liquidation or the sale of all or substantially all of the Company's assets, after payment in full of all amounts required to be paid to creditors and to the holders of preferred stock having liquidation preferences, if any, the holders of the Company's Class A common stock will be entitled to receive pro rata the Company's remaining assets available for distribution. Holders of the Company's Class A common stock do not have preemptive, subscription, redemption or conversion rights. Subject to the transfer restrictions set forth in the 3rd LLC Agreement of D&P Acquisitions, holders of fully vested New Class A Units (other than Duff & Phelps Corporation) may exchange these New Class A Units with D&P Acquisitions for shares of Class A common stock on a one-for-one basis, subject to customary conversion rate adjustments for stock splits, stock dividends and reclassifications. In connection with the closing of the IPO, D&P Acquisitions and certain of its existing unitholders entered into an Exchange Agreement under which, subject to the applicable minimum retained ownership requirements and certain other restrictions, including notice requirements, from time to time, typically once a quarter, such unitholders (or certain transferees thereof) will have the right to exchange with D&P Acquisitions their New Class A Units for shares of the Company's Class A common stock on a one-for-one basis. In connection with an exchange, a corresponding number of shares of the Company's Class B common stock will be required to be cancelled. However, the exchange of New Class A Units for shares of the Company's Class A common stock will not affect the Company's Class B common stockholders' voting power since the votes represented by the cancelled shares of the Company's Class B common stock will be replaced with the votes represented by the shares of Class A common stock for which such New Class A Units are exchanged. As of December 31, 2012, all New Class A Units had either been exchanged or redeemed for shares of the Company's Class A common stock. Class B Common Stock Holders of the Company's Class B common stock are entitled to one vote for each share held of record on all matters submitted to a vote of stockholders. Generally, all matters to be voted on by stockholders must be approved by a majority (or, in the case of election of directors, by a plurality) of the votes entitled to be cast by all shares of Class B common stock and Class A common stock present in person or represented by proxy, voting together as a single class. Except as otherwise provided by law, amendments to the amended and restated certificate of incorporation must be approved by a majority of the combined voting power of all shares of Class B common stock and Class A common stock, voting together as a single class. However, amendments to the certificate of incorporation that would alter or change the powers, preferences or special rights of the Class B common stock so as to affect them adversely also must be approved by a majority of the votes entitled to be cast by the holders of the shares affected by the amendment, voting as a separate class. Notwithstanding the foregoing, any amendment to the Company's amended and restated certificate of incorporation to increase or decrease the authorized shares of any class of common stock shall be approved upon the affirmative vote of the holders of a majority of the shares of Class B common stock and Class A common stock, voting together as a single class. Holders of the Company's Class B common stock will not have any right to receive dividends (other than dividends consisting of shares of the Company's Class B common stock paid proportionally with respect to each outstanding share of the Company's Class B common stock) or to receive a distribution upon a liquidation or winding up of the Company. Holders of the Company's Class B common stock do not have preemptive, subscription, redemption or conversion rights. There were no shares of Class B common stock outstanding at December 31, 2012. Exchanges of New Class A Units to Class A Common Stock In connection with the closing of the IPO, D&P Acquisitions and certain of its existing unitholders entered into an exchange agreement under which, subject to the applicable minimum retained ownership requirements and certain other restrictions, including notice requirements, from time to time, typically once a quarter, such unitholders (or certain transferees thereof) will have the right to exchange with D&P Acquisitions their New Class A Units for shares of the Company's Class A common stock on a one-for-one basis. The Company exchanged 6,081, 653 and 1,788 New Class A Units for a corresponding number of shares of Class A common stock in the years ended December 31, 2012, 2011 and 2010, respectively. In connection with the exchange, a corresponding number of shares of Class B common stock were cancelled. The Company received no other consideration in connection with the exchanges. As of December 31, 2012, all remaining New Class A Units had either been exchanged or redeemed and the corresponding shares of Class B common cancelled.

The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable). Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

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Duff & Phelps Corp 10-K