<SEC-DOCUMENT>0000350894-22-000017-index.html : 20220420
<SEC-HEADER>0000350894-22-000017.hdr.sgml : 20220420
<ACCEPTANCE-DATETIME>20220420160812
ACCESSION NUMBER:		0000350894-22-000017
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		18
CONFORMED PERIOD OF REPORT:	20220419
ITEM INFORMATION:		Results of Operations and Financial Condition
ITEM INFORMATION:		Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20220420
DATE AS OF CHANGE:		20220420

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:		22838105

	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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<TYPE>8-K
<SEQUENCE>1
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Document 1 - file: seic-20220419.htm
</DOCUMENT> <DOCUMENT> <TYPE>EX-99.1 <SEQUENCE>2 <FILENAME>seic-earningsreleaseex9914.htm <DESCRIPTION>PRESS RELEASE DATED APRIL 20, 2022 RELATED TO FIRST QUARTER 2022 EARNINGS <TEXT> Document 2 - file: seic-earningsreleaseex9914.htm
</DOCUMENT> <DOCUMENT> <TYPE>EX-99.2 <SEQUENCE>3 <FILENAME>corpbrassingtonbodappoin.htm <DESCRIPTION>PRESS RELEASE DATED APRIL 20, 2022 RELATED TO BOARD APPOINTMENT <TEXT> Document 3 - file: corpbrassingtonbodappoin.htm
</DOCUMENT> <DOCUMENT> <TYPE>EX-101.SCH <SEQUENCE>4 <FILENAME>seic-20220419.xsd <DESCRIPTION>XBRL TAXONOMY EXTENSION SCHEMA DOCUMENT <TEXT> Document 4 - file: seic-20220419.xsd
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</DOCUMENT> <DOCUMENT> <TYPE>EX-101.PRE <SEQUENCE>6 <FILENAME>seic-20220419_pre.xml <DESCRIPTION>XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE DOCUMENT <TEXT> Document 6 - file: seic-20220419_pre.xml
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</DOCUMENT> <DOCUMENT> <TYPE>XML <SEQUENCE>12 <FILENAME>seic-20220419_htm.xml <DESCRIPTION>IDEA: XBRL DOCUMENT <TEXT> Document 12 - file: seic-20220419_htm.html
Document 12 - RAW XML: seic-20220419_htm.xml
</DOCUMENT> <DOCUMENT> <TYPE>EXCEL <SEQUENCE>13 <FILENAME>Financial_Report.xlsx <DESCRIPTION>IDEA: XBRL DOCUMENT <TEXT> Document 13 - file: Financial_Report.xlsx
</DOCUMENT> <DOCUMENT> <TYPE>XML <SEQUENCE>14 <FILENAME>Show.js <DESCRIPTION>IDEA: XBRL DOCUMENT <TEXT> Document 14 - file: Show.js
</DOCUMENT> <DOCUMENT> <TYPE>XML <SEQUENCE>15 <FILENAME>report.css <DESCRIPTION>IDEA: XBRL DOCUMENT <TEXT> Document 15 - file: report.css
</DOCUMENT> <DOCUMENT> <TYPE>XML <SEQUENCE>16 <FILENAME>FilingSummary.xml <DESCRIPTION>IDEA: XBRL DOCUMENT <TEXT> Document 16 - file: FilingSummary.html
Document 16 - RAW XML: FilingSummary.xml
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