Water dropping from tailpipe while car is idling. Problem?

If it were the gasket then there would be steam billowing from the exhaust depending on how revved the engine was, check the oil too, any water in there would turn the oil a milky brown and again steam would escape from the engine (be very careful if attempting this!).
When gas is burnt in engines the air mixture and the hydrocarbon that makes up the fuel make heat and release energy but the by-product is water, the different chemicals that make up gas vary but simply put;
CH+O = CO2 and H2O.