    <SEC-DOCUMENT>0000105770-21-000003-index.html : 20210218
    <SEC-HEADER>0000105770-21-000003.hdr.sgml : 20210218
    <ACCEPTANCE-DATETIME>20210218073938
    ACCESSION NUMBER:		0000105770-21-000003
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		41
    CONFORMED PERIOD OF REPORT:	20210218
    ITEM INFORMATION:		Results of Operations and Financial Condition
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20210218
    DATE AS OF CHANGE:		20210218

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			WEST PHARMACEUTICAL SERVICES INC
    		CENTRAL INDEX KEY:			0000105770
    		STANDARD INDUSTRIAL CLASSIFICATION:	FABRICATED RUBBER PRODUCTS, NEC [3060]
    		IRS NUMBER:				231210010
    		STATE OF INCORPORATION:			PA
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-08036
    		FILM NUMBER:		21647684

    	BUSINESS ADDRESS:
    		STREET 1:		530 HERMAN O. WEST DRIVE
    		CITY:			EXTON
    		STATE:			PA
    		ZIP:			19341
    		BUSINESS PHONE:		6105942900

    	MAIL ADDRESS:
    		STREET 1:		530 HERMAN O. WEST DRIVE
    		CITY:			EXTON
    		STATE:			PA
    		ZIP:			19341

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	WEST CO INC
    		DATE OF NAME CHANGE:	19990405
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>8-K
    <SEQUENCE>1
    <FILENAME>wst-20210218.htm
    <DESCRIPTION>8-K
    <TEXT>
    Document 1 - file: wst-20210218.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.1
    <SEQUENCE>2
    <FILENAME>exh991q42020earningsreleas.htm
    <DESCRIPTION>EX-99.1
    <TEXT>
    Document 2 - file: exh991q42020earningsreleas.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.2
    <SEQUENCE>3
    <FILENAME>wstq4presentation.htm
    <DESCRIPTION>EX-99.2
    <TEXT>
    Document 3 - file: wstq4presentation.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.SCH
    <SEQUENCE>4
    <FILENAME>wst-20210218.xsd
    <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT
    <TEXT>
    Document 4 - file: wst-20210218.xsd

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.CAL
    <SEQUENCE>5
    <FILENAME>wst-20210218_cal.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION CALCULATION LINKBASE DOCUMENT
    <TEXT>
    Document 5 - file: wst-20210218_cal.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.DEF
    <SEQUENCE>6
    <FILENAME>wst-20210218_def.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION DEFINITION LINKBASE DOCUMENT
    <TEXT>
    Document 6 - file: wst-20210218_def.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.LAB
    <SEQUENCE>7
    <FILENAME>wst-20210218_lab.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION LABEL LINKBASE DOCUMENT
    <TEXT>
    Document 7 - file: wst-20210218_lab.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-101.PRE
    <SEQUENCE>8
    <FILENAME>wst-20210218_pre.xml
    <DESCRIPTION>XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT
    <TEXT>
    Document 8 - file: wst-20210218_pre.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>9
    <FILENAME>exh991logo1.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 9 - file: exh991logo1.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>10
    <FILENAME>wst-20210218_g1.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 10 - file: wst-20210218_g1.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>11
    <FILENAME>wstq4presentation001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 11 - file: wstq4presentation001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>12
    <FILENAME>wstq4presentation002.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 12 - file: wstq4presentation002.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>13
    <FILENAME>wstq4presentation003.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 13 - file: wstq4presentation003.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>14
    <FILENAME>wstq4presentation004.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 14 - file: wstq4presentation004.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>15
    <FILENAME>wstq4presentation005.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 15 - file: wstq4presentation005.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>16
    <FILENAME>wstq4presentation006.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 16 - file: wstq4presentation006.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>17
    <FILENAME>wstq4presentation007.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 17 - file: wstq4presentation007.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>18
    <FILENAME>wstq4presentation008.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 18 - file: wstq4presentation008.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>19
    <FILENAME>wstq4presentation009.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 19 - file: wstq4presentation009.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>20
    <FILENAME>wstq4presentation010.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 20 - file: wstq4presentation010.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>21
    <FILENAME>wstq4presentation011.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 21 - file: wstq4presentation011.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>22
    <FILENAME>wstq4presentation012.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 22 - file: wstq4presentation012.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>23
    <FILENAME>wstq4presentation013.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 23 - file: wstq4presentation013.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>24
    <FILENAME>wstq4presentation014.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 24 - file: wstq4presentation014.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>25
    <FILENAME>wstq4presentation015.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 25 - file: wstq4presentation015.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>26
    <FILENAME>wstq4presentation016.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 26 - file: wstq4presentation016.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>27
    <FILENAME>wstq4presentation017.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 27 - file: wstq4presentation017.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>28
    <FILENAME>wstq4presentation018.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 28 - file: wstq4presentation018.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>29
    <FILENAME>wstq4presentation019.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 29 - file: wstq4presentation019.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>30
    <FILENAME>wstq4presentation020.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 30 - file: wstq4presentation020.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>31
    <FILENAME>wstq4presentation021.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 31 - file: wstq4presentation021.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>32
    <FILENAME>wstq4presentation022.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 32 - file: wstq4presentation022.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>33
    <FILENAME>wstq4presentation023.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 33 - file: wstq4presentation023.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>34
    <FILENAME>wst-20210218_htm.xml
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 34 - file: wst-20210218_htm.html

    Document 34 - RAW XML: wst-20210218_htm.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>35
    <FILENAME>R1.htm
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 35 - file: R1.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EXCEL
    <SEQUENCE>36
    <FILENAME>Financial_Report.xlsx
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 36 - file: Financial_Report.xlsx

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>37
    <FILENAME>Show.js
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 37 - file: Show.js

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>38
    <FILENAME>report.css
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 38 - file: report.css

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>XML
    <SEQUENCE>39
    <FILENAME>FilingSummary.xml
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 39 - file: FilingSummary.html

    Document 39 - RAW XML: FilingSummary.xml

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>JSON
    <SEQUENCE>41
    <FILENAME>MetaLinks.json
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 41 - file: MetaLinks.json

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>ZIP
    <SEQUENCE>42
    <FILENAME>0000105770-21-000003-xbrl.zip
    <DESCRIPTION>IDEA: XBRL DOCUMENT
    <TEXT>
    Document 42 - file: 0000105770-21-000003-xbrl.zip

    </DOCUMENT>
    </SEC-DOCUMENT>