Debt Instrument, Interest Rates Accrual, Number Of Preceding Fiscal Quarters

No definition available.

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- Definition

Line Of Credit Facility, Conditional Increase (Decrease), Net

+ References

No definition available.

+ Details

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Namespace Prefix:	seic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line Of Credit Facility, Fronting Fee Percentage

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
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Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Period Type:	duration

- 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_LineOfCreditFacilityLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Line of Credit (Details) - 2021 Credit Facility	Apr. 23, 2021 USD ($) fiscalQuarter	Apr. 18, 2023 USD ($)
Line of Credit Facility [Line Items]
Debt interest rate accrual term, number of preceding fiscal quarters \| fiscalQuarter	4
Subsequent Event
Line of Credit Facility [Line Items]
Letters of credit outstanding amount		$ 4,866,000
Line of Credit
Line of Credit Facility [Line Items]
Credit facility term of agreement	5 years
Credit facility maximum borrowing capacity	$ 325,000,000
Credit facility stated percentage	0.00%
Credit facility accordion feature, increase limit	$ 100,000,000
Line of Credit \| Subsequent Event
Line of Credit Facility [Line Items]
Credit facility remaining borrowing capacity		$ 320,134,000
Line of Credit \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Credit facility variable interest rate basis spread	1.00%
Line of Credit \| Federal Funds Rate
Line of Credit Facility [Line Items]
Credit facility variable interest rate basis spread	0.50%
Line of Credit \| Minimum
Line of Credit Facility [Line Items]
Credit facility commitment fee per annum on daily unused portion	0.15%
Line of Credit \| Minimum \| Lender's Base Rate Plus Market Spread
Line of Credit Facility [Line Items]
Credit facility variable interest rate basis spread	0.25%
Line of Credit \| Minimum \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Credit facility variable interest rate basis spread	1.25%
Line of Credit \| Maximum
Line of Credit Facility [Line Items]
Credit facility commitment fee per annum on daily unused portion	0.30%
Line of Credit \| Maximum \| Lender's Base Rate Plus Market Spread
Line of Credit Facility [Line Items]
Credit facility variable interest rate basis spread	1.00%
Line of Credit \| Maximum \| London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Credit facility variable interest rate basis spread	2.00%
Letter of Credit
Line of Credit Facility [Line Items]
Credit facility maximum borrowing capacity	$ 15,000,000
Credit facility, commitment fee percentage	1.25%
Credit facility, fronting fee percentage	0.20%