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Adjusted Term SOFR Rate Plus Applicable Margin

No definition available.

Name:	nsp_AdjustedTermSOFRRatePlusApplicableMargin
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Applicable margin to the federal funds rate for alternate base rate borrowings.

No definition available.

Name:	nsp_ApplicableMarginFederalFundsRate
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Percentage of subsidiary stock securing debt per debt agreements.

No definition available.

Name:	nsp_PercentageOfSubsidiaryStockSecuringDebt
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Data Type:	xbrli:decimalItemType
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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

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The effective interest rate during the reporting period.

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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.

No definition available.

Name:	us-gaap_LineOfCreditFacilityLineItems
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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.

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

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Data Type:	xbrli:monetaryItemType
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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
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Data Type:	dtr-types:percentItemType
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Period Type:	duration

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_LongTermDebtNoncurrent
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
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