Condensed Consolidated Statements of Income (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenues	$ 87,886	$ 88,742	$ 172,932	$ 177,906
Reimbursable expenses	3,074	1,962	4,966	4,760
Total revenues	90,960	90,704	177,898	182,666
Direct client service costs
Compensation and benefits (includes $4,130 and $4,215 of equity-based compensation for the three months ended June 30, 2011 and 2010, respectively, and $9,065 and $7,932 for the six months ended June 30, 2011 and 2010, respectively)	49,059	50,415	95,967	99,013
Other direct client service costs	1,480	1,881	2,909	3,869
Acquisition retention expenses (includes $297 and $379 of equity-based compensation for the three and six months ended June 30, 2011)	297	0	379	0
Reimbursable expenses	3,132	2,039	5,069	4,893
Cost of Revenue	53,968	54,335	104,324	107,775
Operating expenses
Selling, general and administrative (includes $769 and $2,005 of equity-based compensation for the three months ended June 30, 2011 and 2010, respectively, and $2,292 and $3,458 for the six months ended June 30, 2011 and 2010, respectively)	24,982	26,304	49,304	50,388
Depreciation and amortization	2,567	2,350	5,056	4,843
Restructuring charges (Note 10)	904	0	904	0
Merger and acquisition costs	272	321	466	321
Charge from impairment of certain intangible assets	0	0	0	674
Operating Expenses	28,725	28,975	55,730	56,226
Operating income	8,267	7,394	17,844	18,665
Other expense/(income), net
Interest income	(27)	(53)	(55)	(77)
Interest expense	91	76	148	168
Other expense/(income)	0	247	(7)	232
Nonoperating expense/(income) including interest expense/income	64	270	86	323
Income before income taxes	8,203	7,124	17,758	18,342
Provision for income taxes	2,556	2,506	5,620	6,156
Net income	5,647	4,618	12,138	12,186
Less: Net income attributable to noncontrolling interest	2,223	2,111	4,601	5,406
Net income attributable to Duff & Phelps Corporation	$ 3,424	$ 2,507	$ 7,537	$ 6,780
Common Stock Class A
Weighted average shares of Class A common stock outstanding
Basic	27,296	25,058	27,104	25,022
Diluted	28,067	25,754	28,095	25,903
Net income per share attributable to stockholders of Class A common stock of Duff & Phelps Corporation (Note 4)
Basic	$ 0.12	$ 0.10	$ 0.27	$ 0.26
Diluted	$ 0.12	$ 0.09	$ 0.26	$ 0.25
Cash dividends declared per common share	$ 0.08	$ 0.06	$ 0.16	$ 0.11