Pros
Top leadership does a great job communicating to employees. Very important given the company size. Great benefits, salaries, pension plan. Large, diverse Fortune 500 company. EXTREME company-wide emphasis on safety. Seriously!!! Don't get caught jaywalking outside during lunch because if they know you work for Duke, they will call you out if they catch you.
Cons
Despite the obvious success of the company, some departments still use outdated practices, technology, etc. Culture clashes. Tenured employees, many whom have been around 30 or 40 years set the standard for how things get done. Lot of them are stuck doing things the "old"way and are resistant to new ideas or outsiders. Despite the size of the company, it feels like its stuck in a time bubble. Not the cutting edge company one would envision. Good ole boy network in full effect in most departments. Blind leading the blind since the merger. Highly ineffective leadership in some departments. Great place to work for someone who wants to coast and get a paycheck.