The interview process varies based on the team that you are being hired onto, typically there are 3-4 rounds of group and individual interviews. There ultimately be an interview with the VP of the corresponding department. The process, and the receipt of the offer letter, often takes months.

First was a phone interview with manager, informal office interview with same manager, HQ interview in Houston, TX with 3 employees and Regional VP. After this lengthy process, never had a formal rejection from manager I had contact with or from HR. I reached out 4 weeks later to confirm that I had not received the job. It was strange to have to do this because of the fact that I was given three interviews, including being flown out of state and put up in a hotel by the company.