The Standard requires that you document the following: (highlighted items offer definition)
Much depends on the size and complexity of your organization. You should have enough procedures to cover each section of the standard that applies to your business.
The ISO/IAF Guidelines says: "The auditee/auditor considers that each clause or sub-clause of ISO 9001 must be defined as a separate process".
Do you purchase anything that could have an impact on meeting the customers' requirements? Then you'll need a Purchasing Procedure to describe section 7.4 - yet that isn't "required".
There are actually 20 different related (ISO 9000) processes called out in the standard. The 9000 Store has designed clearly written procedures to describe each section of the standard. That is why our QMS process is better than the rest - we cover the entire standard. Don't think you can only provide a few procedures and call it an ISO 9000 QMS. The result can be a very poor ISO 9000 process. Is it worth the savings?

Process vs. Procedure vs. Work Instruction
If you look at this pyramid, the lower the items are - the more specific they are to your business. The higher levels (QM, Proc) are dictated by the standard and are thus fairly common from one ISO 9001 company to the next.