How can you add an account category type like Investment or Real Estate?

I see I can select different Account Categories and in those categories I can select the type of account. I don't see how I can add an Account Category or an Account Type in a Category.

For example under the Bank Type I can select Liability but I can't specifically create a Mortgage category and a separate Line of Credit category to separate them as Liabilities.

If the broad scope they are Assets. I can't create a separate category for Life Insurance or Investments such as Mutual Funds or Stocks.

Am I missing an area where these can be created?