1st it was the phone interview second an in person interview. They will either call you to come in person for the second interview or schedule a skype inter if your unable to attend.

4 week process I applied online through an employer referral. I was contacted the same day I applied and was asked if I would be interested in an over the phone interview. That phone interview happened one week after the initial email and was a very brief, they just asked me about previous work experience and explained the job and benefits of the job to me. It lasted about 20 minutes. Right from the phone interview they asked if I could come in for an in person interview. I interviewed in person 2 weeks later. The interview consisted of two 30 minute interviews with a 30 minute job shadowing segment in between the interviews. The questions they asked were basic behavioral questions and my interviewers were very polite and created a non threatening environment.