XML 82 R66.htm IDEA: XBRL DOCUMENT v3.20.4

Commitments and Contingencies (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) lawsuit	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Rent expense | $	$ 9,711	$ 10,159
Number of lawsuits filed	7
Cases with SPTC as Defendant
Loss Contingencies [Line Items]
Number of lawsuits filed	4
Claims for Violations of Louisiana Racketeering Act
Loss Contingencies [Line Items]
Number of lawsuits filed	2
Cases Remaining in Parish of East Baton Rouge Granted Indefinite Extensions to Respond
Loss Contingencies [Line Items]
Number of lawsuits filed	2
Cases Filed in East Baton Rouge
Loss Contingencies [Line Items]
Number of lawsuits filed	2
User licenses for software
Loss Contingencies [Line Items]
Rent expense | $	$ 41,091	$ 33,600
Rent expense | $			$ 34,679

X

- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

Name:	us-gaap_LeaseAndRentalExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

+ Details

Name:	us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918638-209977

+ Details

Name:	us-gaap_OperatingLeaseExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

Name:	srt_LitigationCaseAxis=seic_CasesWithSPTCAsDefendantMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_LitigationCaseAxis=seic_ClaimsForViolationsOfLouisianaRacketeeringActMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_LitigationCaseAxis=seic_CasesRemainingInParishOfEastBatonRougeGrantedIndefiniteExtensionsToRespondMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_LitigationCaseAxis=seic_CasesFiledInEastBatonRougeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LicenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: