U.S. stocks opened lower Monday morning in a busy week for economic and earnings news. The Federal Reserve holds a two day meeting this week, but is not expected to make any changes to interest rate policy. Halliburton (HAL - Get Report) was supposed to report earnings but delayed the release of its results as it works to finalize its deal with Baker Hughes. Valeant (VRX) named a new CEO, Joseph Papa, who joins the company from Perrigo (PRGO - Get Report) . Some M&A activity to kick off the week, as Gannett (GCI - Get Report) offered to buy Tribune (TRBAA)  for $12.25 a share in cash.