No, Tablix took the place of Matrix and is an aggregation tool.

From Applied Microsoft Reporting Services 2008 by Teo Lachev "Tablix lets you author versatile table-style reports with multiple row groups and column groups. Tablix brings in features that were either not supported or difficult to implement in previous releases."

"In previous releases, the Report Designer would display a green triangle in the right top corner of a total

field in a cross-tab (matrix) report. Many developers, including myself, were frustrated because cross-tab totals supported minimal customization through the InScope function and were limited to the Sum aggregation function only. With the Tablix data region these limitations simply disappear."

Tablix is a powerful tool, but displaying detail data is not one of it's functions.

What you CAN do is create a report with the detail information in it, and link that to one of the group fields in the tablix so that when it's clicked, the group acts as a parameter and the detail report opens displaying the detail for that group selection.