Base cars generally had leather seats and not much else in leather, but it can vary a bit with model year and market. Additional leather was an option - typically added to the dash doors, rear quarters, etc. Additional options added it in other places, and through the Exclusive program you could go crazy and have leather everything - knobs, switches, seat belt holders, etc. etc. The option sticker under the right rear hatch carpet on the floor (assuming you have a North American market car) will tell you what options your car came with. Search for the option decoder to translate the numbers to option descriptions.
The additional leather can be a pain - it dries out and pulls up panel edges and really damages the dash in hot climates and was generally discontinued in later models in some markets. Nowadays the 'leather' in many cars is a very thin bonded material, with a coating, that does not have the issues that the full hides used to have.
Cloth seat inserts and door panel inserts were available in some markets too.
