DTE Energy missed quarterly profit estimates as its energy trading unit reported a loss of $25 million compared to the year-ago profit of $34 million. The company has invested over $1.2 billion in its utilities and plans to invest more than $6 billion this year to improve safety and reliability of its electric and natural gas infrastructure. However, the company's electric segment reported a profit $218 million during the period, compared to $147 million a year ago. Additionally, its gas unit saw a 2-2% increase in profit. The utility reaffirmed its full-year operating profit outlook.