Equity	12 Months Ended
Dec. 31, 2013
Stockholders' Equity Note [Abstract]
Equity	Dividends declared per common share were $1.80 for each of the years ended December 31, 2013, 2012 and 2011 and are paid on outstanding common shares. In addition, dividends equivalent amounts are paid on outstanding restricted stock units and amounted to $6.2 million, $5.6 million and $4.8 million for the year ended December 31, 2013, 2012 and 2011, respectively, and are included in dividends paid on the consolidated statements of cash flows. In the event a restricted stock unit holder’s employment is terminated, a portion of the dividend equivalent may be required to be paid back (a "clawback") to the Company and is netted against the dividend equivalent amounts. See “Note 12 — Restricted Stock Units”. During 2013, 693,691 restricted stock units vested and were issued as common stock of which the Company is deemed to have repurchased 226,505 shares at an average price of $56.83 per share in conjunction with the payment of tax liabilities in respect of stock delivered to its employees in settlement of restricted stock units. In addition, during 2013 the Company repurchased in open market transactions 853,870 shares of its common stock at an average price of $49.81. During 2012, 654,612 restricted stock units vested and were issued as common stock of which the Company is deemed to have repurchased 181,820 shares at an average price of $45.29 per share in conjunction with the payment of tax liabilities in respect of stock delivered to its employees in settlement of restricted stock units. In addition, during 2012 the Company repurchased in open market transactions 1,714,614 shares of its common stock at an average price of $43.70. In connection with the acquisition of Greenhill Australia in April 2010, the Company issued 1,099,877 shares of contingent convertible preferred stock ("Performance Stock"). The Performance Stock does not pay dividends, was issued in tranches of 659,926 shares and 439,951 shares, and converts to shares of the Company’s common stock promptly after the third and fifth anniversaries of the closing of the acquisition, respectively, if certain separate revenue targets are achieved. During 2012, the revenue target for the first tranche was achieved and on April 1, 2013, the third anniversary of the closing, 659,926 shares of Performance Stock, which had a fair value of $32.5 million at the acquisition date, were converted to common stock. See "Note 10 — Earnings per Share". In addition, at the closing of the acquisition of Greenhill Australia, the Company granted performance based restricted stock units (“Performance RSUs”), that are subject to the same revenue targets as the Performance Stock. The Performance RSUs vest in tranches of 62,690 and 41,794 shares on the third and fifth anniversaries of the closing, respectively, subject to the achievement of the same revenue targets as the Performance Stock. Amortization of each tranche of the Performance RSUs begins at the time it is deemed probable that the revenue targets will be achieved and the value of the award at that date is amortized over the remaining vesting period of each award. If those revenue targets are not achieved, the Performance RSUs will be canceled and no amount will be expensed. As a result, on April 1, 2013, the revenue target was achieved and 62,690 shares vested. For the years ended December 31, 2013, 2012 and 2011, the Company expensed $0.4 million, $1.7 million and $3.0 million respectively, related to the first tranche of Performance RSUs. The Company did not incur an expense related to the second tranche in the years ended December 31, 2013, 2012 or 2011.

Equity

12 Months Ended

Dec. 31, 2013

Stockholders' Equity Note [Abstract]

Dividends declared per common share were $1.80 for each of the years ended December 31, 2013, 2012 and 2011 and are paid on outstanding common shares. In addition, dividends equivalent amounts are paid on outstanding restricted stock units and amounted to $6.2 million, $5.6 million and $4.8 million for the year ended December 31, 2013, 2012 and 2011, respectively, and are included in dividends paid on the consolidated statements of cash flows. In the event a restricted stock unit holder’s employment is terminated, a portion of the dividend equivalent may be required to be paid back (a "clawback") to the Company and is netted against the dividend equivalent amounts. See “Note 12 — Restricted Stock Units”.

During 2013, 693,691 restricted stock units vested and were issued as common stock of which the Company is deemed to have repurchased 226,505 shares at an average price of $56.83 per share in conjunction with the payment of tax liabilities in respect of stock delivered to its employees in settlement of restricted stock units. In addition, during 2013 the Company repurchased in open market transactions 853,870 shares of its common stock at an average price of $49.81.

During 2012, 654,612 restricted stock units vested and were issued as common stock of which the Company is deemed to have repurchased 181,820 shares at an average price of $45.29 per share in conjunction with the payment of tax liabilities in respect of stock delivered to its employees in settlement of restricted stock units. In addition, during 2012 the Company repurchased in open market transactions 1,714,614 shares of its common stock at an average price of $43.70.

In connection with the acquisition of Greenhill Australia in April 2010, the Company issued 1,099,877 shares of contingent convertible preferred stock ("Performance Stock"). The Performance Stock does not pay dividends, was issued in tranches of 659,926 shares and 439,951 shares, and converts to shares of the Company’s common stock promptly after the third and fifth anniversaries of the closing of the acquisition, respectively, if certain separate revenue targets are achieved. During 2012, the revenue target for the first tranche was achieved and on April 1, 2013, the third anniversary of the closing, 659,926 shares of Performance Stock, which had a fair value of $32.5 million at the acquisition date, were converted to common stock. See "Note 10 — Earnings per Share".

In addition, at the closing of the acquisition of Greenhill Australia, the Company granted performance based restricted stock units (“Performance RSUs”), that are subject to the same revenue targets as the Performance Stock. The Performance RSUs vest in tranches of 62,690 and 41,794 shares on the third and fifth anniversaries of the closing, respectively, subject to the achievement of the same revenue targets as the Performance Stock. Amortization of each tranche of the Performance RSUs begins at the time it is deemed probable that the revenue targets will be achieved and the value of the award at that date is amortized over the remaining vesting period of each award. If those revenue targets are not achieved, the Performance RSUs will be canceled and no amount will be expensed. As a result, on April 1, 2013, the revenue target was achieved and 62,690 shares vested. For the years ended December 31, 2013, 2012 and 2011, the Company expensed $0.4 million, $1.7 million and $3.0 million respectively, related to the first tranche of Performance RSUs. The Company did not incur an expense related to the second tranche in the years ended December 31, 2013, 2012 or 2011.