Yes – both. Often, when drafting a patent application a client does not want to provide details, because they are worried that “the patent will be limited to the details”. However, the opposite is true. A broad patent without details will often fail. A narrow patent without generalities will be narrow.
So, is the combination, a broad patent with a narrow example, enough? No.
One purpose of the patent specification is to show that the inventor had conceived of the invention, in all its breadth and glory, at the time of filing. If the generalities are missing, it can be assumed that the invention was not conceived in as general a form as later claimed. If the details are missing, the application may have no enabling embodiments. If there is only one example, the patent office (especially outside the USA) may insist that the claims must be limited to that single example.
Finally, one must not forget that a general concept may be so broad as to encompass the prior art. If the only fall-back in the patent application is one example, well, that is what you are stuck with.
It should be noted that the USPTO is more flexible than most jurisdictions regarding this issue.
So, did you provide enough details to show that you actually posses the general ideas you are claiming?