$NSP
INSPERITY, INC. Stock $nsp

$nsp Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000100075321000009 Filed on February 12, 2021

Income Statement

Concept	2020 Q4	2019 Q4	2019 Q3
Revenue	$1.056B	$1.075B	$1.043B
YoY Change	-1.75%	11.21%	12.78%
Cost Of Revenue	$888.8M	$913.2M	$872.8M
YoY Change	-2.67%	13.41%	14.98%
Gross Profit	$167.6M	$161.9M	$170.5M
YoY Change	3.5%	0.21%	2.71%
Gross Profit Margin	15.87%	15.06%	16.35%
Selling, General & Admin	$152.0M	$126.4M	$128.5M
YoY Change	20.25%	3.18%	14.43%
% of Gross Profit	90.69%	78.06%	75.35%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$7.900M	$7.800M	$7.300M
YoY Change	1.28%	20.0%	30.36%
% of Gross Profit	4.71%	4.82%	4.28%
Operating Expenses	$159.8M	$134.2M	$135.8M
YoY Change	19.08%	4.11%	15.17%
Operating Profit	$7.800M	$27.72M	$34.73M
YoY Change	-71.86%	-15.02%	-27.84%
Interest Expense	-$1.500M	-$200.0K	$2.122M
YoY Change	650.0%	-114.29%	80.75%
% of Operating Profit	-19.23%	-0.72%	6.11%
Other Income/Expense, Net
YoY Change
Pretax Income	$6.300M	$27.60M	$35.19M
YoY Change	-77.17%	-18.82%	-28.17%
Income Tax	$2.000M	$7.200M	$9.326M
% Of Pretax Income	31.75%	26.09%	26.51%
Net Earnings	$4.300M	$20.40M	$25.86M
YoY Change	-78.92%	-17.28%	-28.58%
Net Earnings / Revenue	0.41%	1.9%	2.48%
Basic Earnings Per Share		$0.51	$0.64
Diluted Earnings Per Share	$112.9K	$0.51	$0.63
COMMON SHARES
Basic Shares Outstanding	38.35M shares	40.00M shares	40.17M shares
Diluted Shares Outstanding			40.32M shares

Balance Sheet

Concept	2020 Q4	2019 Q4	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$589.4M	$402.1M	$304.3M
YoY Change	46.58%	3.74%	-16.84%
Cash & Equivalents	$554.8M	$367.3M	$243.4M
Short-Term Investments	$34.50M	$34.70M	$60.90M
Other Short-Term Assets	$39.46M	$43.49M	$26.44M
YoY Change	-9.27%	56.9%	8.91%
Inventory
Prepaid Expenses
Receivables	$6.559M	$12.73M	$483.9M
Other Receivables	$0.00	$350.9M	$11.70M
Total Short-Term Assets	$1.077B	$974.7M	$893.7M
YoY Change	10.52%	12.49%	5.62%
LONG-TERM ASSETS
Property, Plant & Equipment	$216.3M	$147.7M	$135.0M
YoY Change	46.41%	26.02%	34.04%
Goodwill	$12.70M	$12.70M
YoY Change	0.0%	0.11%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$4.548M	$5.975M	$6.732M
YoY Change	-23.88%	23.17%	18.88%
Total Long-Term Assets	$507.0M	$420.3M	$398.4M
YoY Change	20.64%	29.2%	37.13%
TOTAL ASSETS
Total Short-Term Assets	$1.077B	$974.7M	$893.7M
Total Long-Term Assets	$507.0M	$420.3M	$398.4M
Total Assets	$1.584B	$1.395B	$1.292B
YoY Change	13.57%	17.05%	13.68%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$6.203M	$4.565M	$5.373M
YoY Change	35.88%	-57.02%	1.07%
Accrued Expenses	$60.78M	$58.71M	$42.19M
YoY Change	3.52%	103.23%	71.48%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$904.9M	$869.0M	$761.2M
YoY Change	4.13%	12.52%	9.17%
LONG-TERM LIABILITIES
Long-Term Debt	$369.4M	$269.4M	$239.4M
YoY Change	37.12%	86.57%	129.31%
Other Long-Term Liabilities	$6.292M	$0.00	$0.00
YoY Change		-100.0%	-100.0%
Total Long-Term Liabilities	$635.2M	$521.9M	$489.9M
YoY Change	21.72%	52.68%	70.41%
TOTAL LIABILITIES
Total Short-Term Liabilities	$904.9M	$869.0M	$761.2M
Total Long-Term Liabilities	$635.2M	$521.9M	$489.9M
Total Liabilities	$1.540B	$1.391B	$1.251B
YoY Change	10.73%	24.84%	27.05%
SHAREHOLDERS EQUITY
Retained Earnings	$575.0M	$499.5M	$490.9M
YoY Change	15.13%	25.51%	28.69%
Common Stock	$96.08M	$48.70M	$46.96M
YoY Change	97.31%	30.53%	44.03%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$627.0M	$544.1M	$496.9M
YoY Change	15.23%	52.17%	89.53%
Treasury Stock Shares	17.24M shares	16.12M shares
Shareholders Equity	$44.13M	$4.079M	$40.99M
YoY Change
Total Liabilities & Shareholders Equity	$1.584B	$1.395B	$1.292B
YoY Change	13.57%	17.05%	13.68%

Cashflow Statement

Concept	2020 Q4	2019 Q4	2019 Q3
OPERATING ACTIVITIES
Net Income	$4.300M	$20.40M	$25.86M
YoY Change	-78.92%	-17.28%	-28.58%
Depreciation, Depletion And Amortization	$7.900M	$7.800M	$7.300M
YoY Change	1.28%	20.0%	30.36%
Cash From Operating Activities	$239.8M	$158.1M	-$25.30M
YoY Change	51.68%	38.44%	-147.74%
INVESTING ACTIVITIES
Capital Expenditures	-$29.40M	-$20.30M	-$18.80M
YoY Change	44.83%	47.1%	150.67%
Acquisitions
YoY Change
Other Investing Activities	-$800.0K	$26.20M	$400.0K
YoY Change	-103.05%	-213.91%	-101.31%
Cash From Investing Activities	-$30.20M	$5.900M	-$18.40M
YoY Change	-611.86%	-116.03%	-51.58%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-22.20M	-30.20M	-53.40M
YoY Change	-26.49%	-53.32%	575.95%
NET CHANGE
Cash From Operating Activities	239.8M	158.1M	-25.30M
Cash From Investing Activities	-30.20M	5.900M	-18.40M
Cash From Financing Activities	-22.20M	-30.20M	-53.40M
Net Change In Cash	187.4M	133.8M	-97.10M
YoY Change	40.06%	953.54%	-1467.61%
FREE CASH FLOW
Cash From Operating Activities	$239.8M	$158.1M	-$25.30M
Capital Expenditures	-$29.40M	-$20.30M	-$18.80M
Free Cash Flow	$269.2M	$178.4M	-$6.500M
YoY Change	50.9%	39.38%	-110.74%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001000753
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	38212701	shares
CY2020Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	us-gaap:OtherLiabilitiesCurrent
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	1-13998
CY2020	dei	Entity Registrant Name EntityRegistrantName	Insperity, Inc.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	76-0479645
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	19001 Crescent Springs Drive
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Kingwood,
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	TX
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	77339
CY2020	dei	City Area Code CityAreaCode	281
CY2020	dei	Local Phone Number LocalPhoneNumber	358-8986
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
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CY2020Q2	dei	Entity Public Float EntityPublicFloat	2300000000	USD
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CY2020	us-gaap	Net Income Loss NetIncomeLoss	138237000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	151099000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	135413000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-7000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	21000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-4000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	138230000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	151120000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	135409000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	66321000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	113327000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	0	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	20425000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	-2256000	USD
CY2018	us-gaap	Dividends Common Stock DividendsCommonStock	33408000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-4000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	135413000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	77676000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	203043000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	0	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	23993000	USD
CY2019	us-gaap	Stockholders Equity Other StockholdersEquityOther	-2955000	USD
CY2019	us-gaap	Dividends Common Stock DividendsCommonStock	48622000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	21000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	151099000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	4079000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	99415000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation Gross StockIssuedDuringPeriodValueShareBasedCompensationGross	0	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	60145000	USD
CY2020	us-gaap	Stockholders Equity Other StockholdersEquityOther	-2962000	USD
CY2020	us-gaap	Dividends Common Stock DividendsCommonStock	61869000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-7000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	138237000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	44132000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	138237000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	151099000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	135413000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	31189000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	28723000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	22842000	USD
CY2020	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	-783000	USD
CY2019	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	486000	USD
CY2018	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	-137000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	60145000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	23993000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	20425000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5647000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	4860000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4533000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-73033000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	65156000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	66642000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-254000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	2007000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-2371000	USD
CY2020	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	-4032000	USD
CY2019	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	15772000	USD
CY2018	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	730000	USD
CY2020	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-15725000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-9722000	USD
CY2018	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	2005000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	1638000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	-6057000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	4175000	USD
CY2020	us-gaap	Increase Decrease In Other Employee Related Liabilities IncreaseDecreaseInOtherEmployeeRelatedLiabilities	100712000	USD
CY2019	us-gaap	Increase Decrease In Other Employee Related Liabilities IncreaseDecreaseInOtherEmployeeRelatedLiabilities	16082000	USD
CY2018	us-gaap	Increase Decrease In Other Employee Related Liabilities IncreaseDecreaseInOtherEmployeeRelatedLiabilities	-42081000	USD
CY2020	nsp	Increase Decreasein Wse Epayrollexpense IncreaseDecreaseinWSEEpayrollexpense	-67023000	USD
CY2019	nsp	Increase Decreasein Wse Epayrollexpense IncreaseDecreaseinWSEEpayrollexpense	71880000	USD
CY2018	nsp	Increase Decreasein Wse Epayrollexpense IncreaseDecreaseinWSEEpayrollexpense	62577000	USD
CY2020	us-gaap	Increase Decrease In Health Care Insurance Liabilities IncreaseDecreaseInHealthCareInsuranceLiabilities	11505000	USD
CY2019	us-gaap	Increase Decrease In Health Care Insurance Liabilities IncreaseDecreaseInHealthCareInsuranceLiabilities	-13973000	USD
CY2018	us-gaap	Increase Decrease In Health Care Insurance Liabilities IncreaseDecreaseInHealthCareInsuranceLiabilities	9078000	USD
CY2020	us-gaap	Increase Decrease In Workers Compensation Liabilities IncreaseDecreaseInWorkersCompensationLiabilities	-3052000	USD
CY2019	us-gaap	Increase Decrease In Workers Compensation Liabilities IncreaseDecreaseInWorkersCompensationLiabilities	13247000	USD
CY2018	us-gaap	Increase Decrease In Workers Compensation Liabilities IncreaseDecreaseInWorkersCompensationLiabilities	23763000	USD
CY2020	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	-20763000	USD
CY2019	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	-6386000	USD
CY2018	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	8941000	USD
CY2020	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	5585000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-4616000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	10749000	USD
CY2020	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	208116000	USD
CY2019	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	54054000	USD
CY2018	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	49067000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	346353000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	205153000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	184480000	USD
CY2020	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	50624000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	110131000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	87887000	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	49635000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	108380000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	12625000	USD
CY2020	nsp	Marketable Securities Proceeds From Dispositions MarketableSecuritiesProceedsFromDispositions	484000	USD
CY2019	nsp	Marketable Securities Proceeds From Dispositions MarketableSecuritiesProceedsFromDispositions	28313000	USD
CY2018	nsp	Marketable Securities Proceeds From Dispositions MarketableSecuritiesProceedsFromDispositions	16299000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	98159000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	56307000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	35328000	USD
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	43000	USD
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	21000	USD
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	151000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-98621000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-29724000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-94140000	USD
CY2020	nsp	Treasury Stock Acquired TreasuryStockAcquired	99415000	USD
CY2019	nsp	Treasury Stock Acquired TreasuryStockAcquired	203043000	USD
CY2018	nsp	Treasury Stock Acquired TreasuryStockAcquired	113327000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	61869000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	549612000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	48622000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	33408000	USD
CY2020	us-gaap	Proceeds From Secured Lines Of Credit ProceedsFromSecuredLinesOfCredit	100000000	USD
CY2019	us-gaap	Proceeds From Secured Lines Of Credit ProceedsFromSecuredLinesOfCredit	125000000	USD
CY2018	us-gaap	Proceeds From Secured Lines Of Credit ProceedsFromSecuredLinesOfCredit	40000000	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	7701000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	8312000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	2257000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-53583000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-118353000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-104478000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	194149000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	57076000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-14138000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	592550000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	535474000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	786699000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	592550000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	535474000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	367342000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	326773000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	354260000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	49295000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	42227000	USD
CY2017Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	41137000	USD
CY2019Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	175913000	USD
CY2018Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	166474000	USD
CY2017Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	154215000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	592550000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	535474000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	549612000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	554846000	USD
CY2020Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	186331000	USD
CY2019Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	175913000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	367342000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	326773000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	45522000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	49295000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	42227000	USD
CY2018Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	166474000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	786699000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	592550000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	535474000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	51097000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	38299000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	40730000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	8977000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	7421000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	4006000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	22770000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	24474000	USD
CY2018	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4287004000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	4314804000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3828549000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:10pt;margin-top:10pt"><span style="color:#4c8c2b;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-bottom:10pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with United States Generally Accepted Accounting Principles requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ from those estimates.</span></div>
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="margin-bottom:10pt;margin-top:10pt"><span style="color:#4c8c2b;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Concentrations of Credit Risk</span></div><div style="margin-bottom:10pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Financial instruments that could potentially subject us to concentration of credit risk include accounts receivable and marketable securities.</span></div>
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	495078000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	403301000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	278822000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	255595000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	216256000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	147706000	USD
CY2020	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	8700000	USD
CY2019	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	7800000	USD
CY2018	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	6000000.0	USD
CY2020Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	32600000	USD
CY2019Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	25800000	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	50800000	USD
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	63700000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Goodwill Gross GoodwillGross	21200000	USD
CY2020Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	8500000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	12700000	USD
CY2020Q4	nsp	Percentageofourhealthinsurancecoverageprovidedby United PercentageofourhealthinsurancecoverageprovidedbyUnited	0.87
CY2020	nsp	Number Of Days In Advance Of Beginning Of Reporting Quarter Carrier Establishes Cash Funding Rates NumberOfDaysInAdvanceOfBeginningOfReportingQuarterCarrierEstablishesCashFundingRates	P90D
CY2020Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000.0	USD
CY2020Q4	nsp	Required Deposit For Health Care Costs RequiredDepositForHealthCareCosts	6500000	USD
CY2020Q4	nsp	Prepaid Health Insurance Current And Noncurrent PrepaidHealthInsuranceCurrentAndNoncurrent	-6000000.0	USD
CY2020Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000.0	USD
CY2020Q4	nsp	Portionofinsurancecoststhatislessthantheagreeduponsurplusincludedinaccruedhealthinsurancecostsacntliab Portionofinsurancecoststhatislessthantheagreeduponsurplusincludedinaccruedhealthinsurancecostsacntliab	-15000000.0	USD
CY2020Q4	nsp	Premiums Owed To United PremiumsOwedToUnited	11700000	USD
CY2020Q4	nsp	Benefits Costs Incurred Relatedto Runoff BenefitsCostsIncurredRelatedtoRunoff	-200000	USD
CY2019Q4	nsp	Benefits Costs Incurred Relatedto Runoff BenefitsCostsIncurredRelatedtoRunoff	2300000	USD
CY2018Q4	nsp	Benefits Costs Incurred Relatedto Runoff BenefitsCostsIncurredRelatedtoRunoff	-1300000	USD
CY2010Q3	nsp	Workers Compensation Maximum Economic Burden First Layer Of Claims Per Occurrence WorkersCompensationMaximumEconomicBurdenFirstLayerOfClaimsPerOccurrence	1000000	USD
CY2010Q3	nsp	Workers Compensation Maximum Economic Burden First Layer Of Claims Per Occurrence WorkersCompensationMaximumEconomicBurdenFirstLayerOfClaimsPerOccurrence	1000000	USD
CY2010Q4	nsp	Workers Compensation Maximum Aggregate Economic Burden For Claims In Excess Of First Layer Cap Per Policy Year WorkersCompensationMaximumAggregateEconomicBurdenForClaimsInExcessOfFirstLayerCapPerPolicyYear	6000000	USD
CY2010Q3	nsp	Workers Compensation Maximum Economic Burden First Layer Of Claims Per Occurrence WorkersCompensationMaximumEconomicBurdenFirstLayerOfClaimsPerOccurrence	1000000	USD
CY2019Q4	nsp	Workers Compensation Maximum Economic Burden First Layer Of Claims Per Occurrence WorkersCompensationMaximumEconomicBurdenFirstLayerOfClaimsPerOccurrence	1500000	USD
CY2019Q4	nsp	Workers Compensation Maximum Economic Burden First Layer Of Claims Per Occurrence WorkersCompensationMaximumEconomicBurdenFirstLayerOfClaimsPerOccurrence	1500000	USD
CY2019Q4	nsp	Workers Compensation Maximum Aggregate Economic Burden For Claims In Excess Of First Layer Cap Per Policy Year WorkersCompensationMaximumAggregateEconomicBurdenForClaimsInExcessOfFirstLayerCapPerPolicyYear	6000000	USD
CY2019Q4	nsp	Workers Compensation Maximum Economic Burden First Layer Of Claims Per Occurrence WorkersCompensationMaximumEconomicBurdenFirstLayerOfClaimsPerOccurrence	1500000	USD
CY2020	nsp	Decrease Increase In Accrued Workers Compensation Costs For Changes In Estimated Losses DecreaseIncreaseInAccruedWorkersCompensationCostsForChangesInEstimatedLosses	42100000	USD
CY2019	nsp	Decrease Increase In Accrued Workers Compensation Costs For Changes In Estimated Losses DecreaseIncreaseInAccruedWorkersCompensationCostsForChangesInEstimatedLosses	31700000	USD
CY2018	nsp	Decrease Increase In Accrued Workers Compensation Costs For Changes In Estimated Losses DecreaseIncreaseInAccruedWorkersCompensationCostsForChangesInEstimatedLosses	18800000	USD
CY2020	nsp	Us Treasury Rates That Correspond With Weighted Average Estimated Claim Payout Period USTreasuryRatesThatCorrespondWithWeightedAverageEstimatedClaimPayoutPeriod	0.006
CY2019	nsp	Us Treasury Rates That Correspond With Weighted Average Estimated Claim Payout Period USTreasuryRatesThatCorrespondWithWeightedAverageEstimatedClaimPayoutPeriod	0.019
CY2020	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following table provides the activity and balances related to incurred but not paid workers’ compensation claims:</span></div><div style="margin-top:5pt"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:98.224%"><tr><td style="width:1.0%"/><td style="width:73.030%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.834%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.836%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="6" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#4c8c2b;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Year Ended December 31,</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#4c8c2b;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:100%">(in thousands)</span></td><td colspan="3" style="border-top:1pt solid #4c8c2b;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#4c8c2b;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="border-top:1pt solid #4c8c2b;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#4c8c2b;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">2019</span></td></tr><tr style="height:6pt"><td colspan="3" style="border-top:1pt solid #4c8c2b;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #4c8c2b;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #4c8c2b;padding:0 1pt"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Beginning balance</span></td><td style="padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">242,904 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">229,639 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Accrued claims</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">42,639 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">62,552 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Present value discount, net of accretion</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">740 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(3,643)</span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Paid claims</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(45,522)</span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(45,644)</span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Ending balance</span></td><td style="border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">$</span></td><td style="border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">240,761</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">$</span></td><td style="border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">242,904</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:14pt"><td colspan="3" style="border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="border-top:3pt double #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Current portion of accrued claims</span></td><td style="padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">45,522 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">49,295 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Long-term portion of accrued claims</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">195,239 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%">193,609 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Total accrued claims</span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">$</span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">240,761</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">$</span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:700;line-height:100%">242,904</span><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> </span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div>
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Opening Balance Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseOpeningBalanceAdjustments	242904000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Opening Balance Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseOpeningBalanceAdjustments	229639000	USD
CY2020	nsp	Workers Compensation Expense WorkersCompensationExpense	42639000	USD
CY2019	nsp	Workers Compensation Expense WorkersCompensationExpense	62552000	USD
CY2020	nsp	Workers Compensation Discount Changed During Period WorkersCompensationDiscountChangedDuringPeriod	-740000	USD
CY2019	nsp	Workers Compensation Discount Changed During Period WorkersCompensationDiscountChangedDuringPeriod	3643000	USD
CY2020	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	45522000	USD
CY2019	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	45644000	USD
CY2020Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	240761000	USD
CY2019Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	242904000	USD
CY2020Q4	nsp	Workers Compensation Liability Current Net WorkersCompensationLiabilityCurrentNet	45522000	USD
CY2019Q4	nsp	Workers Compensation Liability Current Net WorkersCompensationLiabilityCurrentNet	49295000	USD
CY2020Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	195239000	USD
CY2019Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	193609000	USD
CY2020Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	240761000	USD
CY2019Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	242904000	USD
CY2020Q4	nsp	Workers Compensation Administrative Fees Accrued WorkersCompensationAdministrativeFeesAccrued	2700000	USD
CY2019Q4	nsp	Workers Compensation Administrative Fees Accrued WorkersCompensationAdministrativeFeesAccrued	3600000	USD
CY2020	nsp	Undiscounted Accrued Workers Compensation Costs UndiscountedAccruedWorkersCompensationCosts	257900000	USD
CY2019	nsp	Undiscounted Accrued Workers Compensation Costs UndiscountedAccruedWorkersCompensationCosts	262900000	USD
CY2020	nsp	Time Period Incurred Claims Expected To Be Paid Recorded As Restricted Cash TimePeriodIncurredClaimsExpectedToBePaidRecordedAsRestrictedCash	P1Y
CY2020	nsp	Return Of Excess Claim Funds ReturnOfExcessClaimFunds	28200000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	45500000	USD
CY2020Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	186300000	USD
CY2020	nsp	Time Period Estimate Of Incurred Claim Costs To Be Paid Included In Short Term Liabilities TimePeriodEstimateOfIncurredClaimCostsToBePaidIncludedInShortTermLiabilities	P1Y
CY2020Q4	nsp	Number Of Stock Based Employee Compensation Plans NumberOfStockBasedEmployeeCompensationPlans	1
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P3Y
CY2020	nsp	Percentageofgrantsissuedtodirectorsthatarevestedforannualawardgrants. Percentageofgrantsissuedtodirectorsthatarevestedforannualawardgrants.	1
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P3Y
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P3Y
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="margin-bottom:10pt;margin-top:10pt"><span style="color:#4c8c2b;font-family:'Arial',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Reclassifications</span></div><div style="margin-bottom:10pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Certain immaterial prior year amounts have been reclassified to conform to the 2020 presentation.</span></div>
CY2020Q4	srt	Drafts Payable DraftsPayable	30059000	USD
CY2020Q4	us-gaap	Short Term Investments ShortTermInvestments	82521000	USD
CY2019Q4	us-gaap	Short Term Investments ShortTermInvestments	47946000	USD
CY2020Q4	us-gaap	Cash Cash	33692000	USD
CY2019Q4	us-gaap	Cash Cash	36521000	USD
CY2020Q4	nsp	Money Market Funds Overnight Holdings At Carrying Value MoneyMarketFundsOvernightHoldingsAtCarryingValue	503221000	USD
CY2019Q4	nsp	Money Market Funds Overnight Holdings At Carrying Value MoneyMarketFundsOvernightHoldingsAtCarryingValue	349857000	USD
CY2019Q4	srt	Drafts Payable DraftsPayable	32254000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents And Short Term Investments CashCashEquivalentsAndShortTermInvestments	589375000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents And Short Term Investments CashCashEquivalentsAndShortTermInvestments	402070000	USD
CY2020Q4	nsp	Payroll Withholdings Included In Cash Balance PayrollWithholdingsIncludedInCashBalance	342000000.0	USD
CY2019Q4	nsp	Payroll Withholdings Included In Cash Balance PayrollWithholdingsIncludedInCashBalance	234600000	USD
CY2020Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	35300000	USD
CY2019Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	465779000	USD
CY2019Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	59600000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	551213000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	363075000	USD
CY2020Q4	us-gaap	Us Government Securities At Carrying Value USGovernmentSecuritiesAtCarryingValue	10531000	USD
CY2019Q4	us-gaap	Us Government Securities At Carrying Value USGovernmentSecuritiesAtCarryingValue	34728000	USD
CY2020Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	23998000	USD
CY2019Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	0	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	585742000	USD
CY2019Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	397803000	USD
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	6559000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	12731000	USD
CY2020Q4	nsp	Unbilled Unbilled	380819000	USD
CY2019Q4	nsp	Unbilled Unbilled	448088000	USD
CY2020Q4	us-gaap	Other Receivables OtherReceivables	5368000	USD
CY2019Q4	us-gaap	Other Receivables OtherReceivables	4960000	USD
CY2020Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	392746000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1000000.0	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	900000	USD
CY2020Q4	nsp	Unbilled Accrued Worksite Employee Payroll Costs UnbilledAccruedWorksiteEmployeePayrollCosts	334836000	USD
CY2019Q4	nsp	Unbilled Accrued Worksite Employee Payroll Costs UnbilledAccruedWorksiteEmployeePayrollCosts	401859000	USD
CY2020Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	81311000	USD
CY2019Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	105841000	USD
CY2020Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	35328000	USD
CY2019Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	59612000	USD
CY2020Q4	nsp	Unbilled Unbilled	380819000	USD
CY2019Q4	nsp	Unbilled Unbilled	448088000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	369400000	USD
CY2020Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000	USD
CY2019Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000	USD
CY2020Q4	nsp	Deposits Health Insurance DepositsHealthInsurance	7900000	USD
CY2019Q4	nsp	Deposits Health Insurance DepositsHealthInsurance	8100000	USD
CY2020Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	186331000	USD
CY2019Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	175913000	USD
CY2020Q4	nsp	Depositsandprepaidhealthinsurance Depositsandprepaidhealthinsurance	203231000	USD
CY2019Q4	nsp	Depositsandprepaidhealthinsurance Depositsandprepaidhealthinsurance	193013000	USD
CY2020Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000.0	USD
CY2020Q3	us-gaap	Line Of Credit Facility Current Borrowing Capacity LineOfCreditFacilityCurrentBorrowingCapacity	500000000	USD
CY2020Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	550000000	USD
CY2020	nsp	Percentage Of Subsidiary Stock Securing Debt PercentageOfSubsidiaryStockSecuringDebt	0.65
CY2020Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	1000000.0	USD
CY2020Q4	us-gaap	Long Term Debt Maturity Date LongTermDebtMaturityDate	2024-09-13
CY2020Q4	nsp	Applicable Margin Federal Funds Rate ApplicableMarginFederalFundsRate	0.0050
CY2020Q4	nsp	Applicable Margin30 Day Libor ApplicableMargin30DayLibor	0.0200
CY2020	us-gaap	Line Of Credit Facility Unused Capacity Commitment Fee Percentage LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage	0.0025
CY2020	us-gaap	Debt Instrument Interest Rate During Period DebtInstrumentInterestRateDuringPeriod	0.024
CY2020Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	4207000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	4252000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	4941000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	4564000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Software DeferredTaxLiabilitiesDeferredExpenseCapitalizedSoftware	8230000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Software DeferredTaxLiabilitiesDeferredExpenseCapitalizedSoftware	6475000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3702000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3209000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	17322000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	15949000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	1444000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	955000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	39846000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	35404000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	5092000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	5946000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	558000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	632000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Self Insurance DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance	6310000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Self Insurance DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance	5404000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	1553000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	1223000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	11383000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	6712000	USD
CY2020Q4	nsp	Deferred Tax Assets Operating Lease Liablities DeferredTaxAssetsOperatingLeaseLiablities	21024000	USD
CY2019Q4	nsp	Deferred Tax Assets Operating Lease Liablities DeferredTaxAssetsOperatingLeaseLiablities	19158000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	3956000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	676000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	673000	USD
CY2020Q4	nsp	Cares Act Dta CARESActDTA	3235000	USD
CY2019Q4	nsp	Cares Act Dta CARESActDTA	0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	294000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	287000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	50125000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	40035000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	676000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	675000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	49449000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	39360000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	9603000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	45558000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	27385000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	40347000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	11122000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	6299000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	11133000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	56680000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	33684000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	51480000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-4678000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	4016000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-3398000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-969000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	844000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1135000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5647000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	4860000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4533000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51033000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	38544000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	46947000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	2100000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	14600000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	3900000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	39747000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	39825000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	38296000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	7818000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	5821000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	7660000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	3641000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	5959000	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	4831000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	1335000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-12120000	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-2737000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Credits Research IncomeTaxReconciliationTaxCreditsResearch	1479000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Credits Research IncomeTaxReconciliationTaxCreditsResearch	1069000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Credits Research IncomeTaxReconciliationTaxCreditsResearch	856000	USD
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-29000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	128000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-247000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51033000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	38544000	USD
CY2020Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.40
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	46947000	USD
CY2020Q4	us-gaap	Liability For Uncertain Tax Positions Current LiabilityForUncertainTaxPositionsCurrent	0	USD
CY2020	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1285696	shares
CY2020	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	151332	shares
CY2020Q4	us-gaap	Stock Repurchase Program Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased	2000000	shares
CY2019	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1897322	shares
CY2019	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	227208	shares
CY2020Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	1128137	shares
CY2020Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.40
CY2019Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.40
CY2019Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.40
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2019Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	61900000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	48600000	USD
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	20000000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	1417062	shares
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	60145000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	23993000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	20425000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	16217000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4876000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5249000	USD
CY2020	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	57000	shares
CY2019	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	29000	shares
CY2018	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	30000	shares
CY2020	us-gaap	Net Income Loss NetIncomeLoss	138237000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	151099000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	135413000	USD
CY2020	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	782000	USD
CY2019	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	1759000	USD
CY2018	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	1875000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	137455000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	149340000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	133538000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	38503000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	40186000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	41217000	shares
CY2020	nsp	Incremental Shares From Assumed Conversions Of Common Stock Options IncrementalSharesFromAssumedConversionsOfCommonStockOptions	317000	shares
CY2019	nsp	Incremental Shares From Assumed Conversions Of Common Stock Options IncrementalSharesFromAssumedConversionsOfCommonStockOptions	166000	shares
CY2018	nsp	Incremental Shares From Assumed Conversions Of Common Stock Options IncrementalSharesFromAssumedConversionsOfCommonStockOptions	289000	shares
CY2020	nsp	Adjusted Weighted Average Common Shares Outstanding AdjustedWeightedAverageCommonSharesOutstanding	38820000	shares
CY2019	nsp	Adjusted Weighted Average Common Shares Outstanding AdjustedWeightedAverageCommonSharesOutstanding	40352000	shares
CY2018	nsp	Adjusted Weighted Average Common Shares Outstanding AdjustedWeightedAverageCommonSharesOutstanding	41506000	shares
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	133000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2020	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	17300000	USD
CY2019	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	15900000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	15400000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	19100000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	60663000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	16518000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	64289000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80807000	USD
CY2020Q4	nsp	Landlordfundedtenantimprovements Landlordfundedtenantimprovements	14189000	USD
CY2020Q4	us-gaap	Deferred Rent Credit Noncurrent DeferredRentCreditNoncurrent	5955000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	60663000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P5Y
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.040
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Rolling Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextRollingTwelveMonths	19384000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	18444000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	15828000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	12791000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	9237000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	14306000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	89990000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	9183000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	80807000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Lease Not Yet Commenced Assumption And Judgment Value Of Underlying Asset Amount LessorOperatingLeaseLeaseNotYetCommencedAssumptionAndJudgmentValueOfUnderlyingAssetAmount	16500000	USD
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	24580000	USD
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	12792000	USD
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary	3633000	USD
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary	1283000	USD
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fifth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary	665000	USD
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	329000	USD
CY2020Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance Sheet Amount UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount	43282000	USD
CY2020	us-gaap	Loss Contingency Damages Sought Value LossContingencyDamagesSoughtValue	146000000.0	USD

Files In Submission

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$NSP
INSPERITY, INC. Stock $nsp

2020 Q4 Form 10-K Financial Statement

#000100075321000009 Filed on February 12, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NSP INSPERITY, INC. Stock $nsp

2020 Q4 Form 10-K Financial Statement

#000100075321000009 Filed on February 12, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NSP
INSPERITY, INC. Stock $nsp