Clarity

I have an idea on which actual are written. Due to which I am unable to delete idea.

Is there any way wherein I can delete the actuals and then delete the idea?

To reverse the actuals you have to either reverse via transaction or adjust the timesheet.

I'm not sure if this will work since the adjusted timesheet will still show the idea.  You would have to adjust the timesheet to get rid of the actuals. Once you have done that, you may be able to delete the idea, but I don't know if it will let you, since the original timesheet will still exist in the system.