What: Shares of Total System Services, (NYSE:TSS) are dropping today on the back of lower-than-expected earnings. Shares are trading down about 12% as of 1:25 p.m. EST.

So what: The company reported adjusted earnings of $0.57 per share, a decrease of 1.6% from the year-ago period, missing analyst expectations of $0.60 per share for the fourth quarter.

Separately, the company announced that it would acquire TransFirst from Vista Equity Partners in an all-cash deal that values the company at about $2.35 billion. TransFirst gives Total System Services more than 235,000 more small and medium-sized business clients in payments, and will make the combined company the sixth-largest U.S. acquirer based on net revenue.

Now what: A slight earnings miss probably wouldn't have been so concerning to Wall Street if it hadn't followed the announcement of an acquisition. S&P downgraded Total System Services from a BBB+ credit to BBB-, noting that the acquisition would increase the company's leverage to the "high-3x area," up from "about 1.5x."