My employer now provides life insurance as an employee benefit. Isn't this sufficent for my needs?

When group term insurance is provided through your employer, the employer may pay for most (and in some cases all) of the premiums.  The amount of your coverage is typically equal to one or two times your annual salary.  Group term coverage remains in force until your employment is terminated, or until the specific term of coverage ends.  Generally, you have the option to convert your group coverage to an individual policy if you leave your employer.  However, most people choose not to do this because individual premiums tend to be much higher than group premiums.  Typically, only those who are otherwise uninsurable take advantage of this conversion option.  If you are healthy, you can usually do far better as an individual while also obtaining greater benefits in terms of exchange and conversion privilege.