Segment Information	12 Months Ended
Dec. 31, 2011
Segment Information [Abstract]
Segment Information	13. Segment Information As an electronic multi-dealer platform for the trading of fixed-income securities, the Company’s operations constitute a single business segment. Because of the highly integrated nature of the financial markets in which the Company competes and the integration of the Company’s worldwide business activities, the Company believes that results by geographic region or client sector are not necessarily meaningful in understanding its business.

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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+ Details