<SEC-DOCUMENT>0000350894-19-000055-index.html : 20191210
<SEC-HEADER>0000350894-19-000055.hdr.sgml : 20191210
<ACCEPTANCE-DATETIME>20191210135910
ACCESSION NUMBER:		0000350894-19-000055
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		17
CONFORMED PERIOD OF REPORT:	20191209
ITEM INFORMATION:		Other Events
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20191210
DATE AS OF CHANGE:		20191210

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SEI INVESTMENTS CO
		CENTRAL INDEX KEY:			0000350894
		STANDARD INDUSTRIAL CLASSIFICATION:	SECURITY BROKERS, DEALERS & FLOTATION COMPANIES [6211]
		IRS NUMBER:				231707341
		STATE OF INCORPORATION:			PA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-10200
		FILM NUMBER:		191277258

	BUSINESS ADDRESS:	
		STREET 1:		1 FREEDOM VALLEY DRIVE
		CITY:			OAKS
		STATE:			PA
		ZIP:			19456-1100
		BUSINESS PHONE:		6106761000

	MAIL ADDRESS:	
		STREET 1:		1 FREEDOM VALLEY DRIVE
		CITY:			OAKS
		STATE:			PA
		ZIP:			19456-1100

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SEI INVESTMENT CO
		DATE OF NAME CHANGE:	20040806

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SEI CORP
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
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Document 1 - file: form8-k12x10x2019.htm

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Document 2 - file: form8-k12x11x18exh991.htm

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<DOCUMENT>
<TYPE>EX-101.SCH
<SEQUENCE>3
<FILENAME>seic-20191210.xsd
<DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT
<TEXT>
Document 3 - file: seic-20191210.xsd

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<TYPE>EX-101.CAL
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Document 4 - file: seic-20191210_cal.xml

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Document 5 - file: seic-20191210_def.xml

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Document 6 - file: seic-20191210_lab.xml

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<TEXT>
Document 15 - file: MetaLinks.json

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<TYPE>EXCEL
<SEQUENCE>16
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Document 16 - file: Financial_Report.xlsx

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