Stocks finished higher Wednesday, although volume appeared to be lighter than the prior day, as the Dow Jones industrial average and the S&P 500 notched new all-time highs. The Nasdaq and the S&P 500 rose 0.4%, while the Dow gained 0.2%. In the stock market today, among IBD 50 stocks the best performer was Ambarella (AMBA), up nearly 6% after Stifel Nicolaus raised its price target to 62 from 47. The stock trades near 56.