U.S. stocks ended higher on Thursday on light volume as investors held out hope the crisis in Ukraine will not escalate. Perrigo (PRGO), a maker of generic over-the-counter drugs was the S&P 500's biggest gainer. Boeing (BA) and Proctor and Gamble (PG) were the blue chip's biggest advancers. Tesla (TSLA) shares managed to close at a fourth straight record. The electric-car maker added to gains after Credit Suisse (CS) became the latest Wall Street firm to issue a positive report on the company. But, a disappointing report on earnings from Red Robin Gourmet Burgers (RRGB) pushed shares down more than 18%. On Friday, as earnings season winds down, investors will get quarterly reports from Estee Lauder (EL). TheStreet's Susannah Lee reports from New York.