Since gaining its independence in 2012, refining giant Phillips 66 (NYSE: PSX) has significantly outperformed the S&P 500, delivering a better-than-225% total return versus the approximately 100% gain of the index. One of the drivers of that outperformance is that the company has returned $12 billion in cash to investors via dividends and share repurchases. More cash is on the way because the company is putting the finishing touches on a major expansion program.