Google doesn't have any hard-and-fast "standards" of what constitutes "good content" or "enough content." It's not like you have a website with 99 pages of content and Google says, that's not "enough" content for us to be happy with you, but when you create that 100th page of content, all of a sudden you shoot up to the top of the rankings because you've passed some Google threshold for "enough" content.
Does your content address the interests and needs of your site visitors? Does it relate to your products or services? Does it work to generate additional business for you? Does it appropriately incorporate the search phrases people use when they're seeking what you offer? Does it cover all potentially relevant topics associated with your product or service? Is it coherent, unique, well-written and grammatically correct? Does each page include a call to action and guide visitors toward your most-desired response?
If so, then it's good content.
As to how much is "enough", that's a bit like asking "how long is a piece of string?"
When you've said everything that ever needs to be said about your product or service, then you've got "enough." As long as there's something additional you can say, or old information that's changed and needs to be updated, then you're not done yet.
There's really no such thing as a "finished" website, IMO.
--Torka