0000105770 2019-09-27 2019-09-27 false 0000105770 8-K 2019-09-27 WEST PHARMACEUTICAL SERVICES, INC. PA 1-8036 23-1210010 530 Herman O. West Drive, Exton, PA 19341-0645 610 594-2900 false false false false Common Stock, par value $0.25 per share WST NYSE false