$NSP
INSPERITY, INC. Stock $nsp

$nsp Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000100075320000013 Filed on February 12, 2020

Income Statement

Concept	2019 Q4	2019	2018 Q4
Revenue	$1.075B	$4.315B	$966.8M
YoY Change	11.21%	12.7%	16.97%
Cost Of Revenue	$913.2M	$3.582B	$805.2M
YoY Change	13.41%	13.83%	17.79%
Gross Profit	$161.9M	$732.9M	$161.6M
YoY Change	0.21%	7.48%	13.11%
Gross Profit Margin	15.06%	16.99%	16.71%
Selling, General & Admin	$126.4M	$517.6M	$122.5M
YoY Change	3.18%	7.83%	7.17%
% of Gross Profit	78.06%	70.62%	75.81%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$7.800M	$28.72M	$6.500M
YoY Change	20.0%	25.75%	35.42%
% of Gross Profit	4.82%	3.92%	4.02%
Operating Expenses	$134.2M	$546.3M	$128.9M
YoY Change	4.11%	8.64%	8.14%
Operating Profit	$27.72M	$186.6M	$32.62M
YoY Change	-15.02%	4.24%	37.56%
Interest Expense	-$200.0K	$7.647M	$1.400M
YoY Change	-114.29%	63.82%	250.0%
% of Operating Profit	-0.72%	4.1%	4.29%
Other Income/Expense, Net
YoY Change
Pretax Income	$27.60M	$189.6M	$34.00M
YoY Change	-18.82%	3.99%	41.08%
Income Tax	$7.200M	$38.54M	$9.300M
% Of Pretax Income	26.09%	20.32%	27.35%
Net Earnings	$20.40M	$151.1M	$24.66M
YoY Change	-17.28%	11.58%	58.51%
Net Earnings / Revenue	1.9%	3.5%	2.55%
Basic Earnings Per Share	$0.51	$3.72	$0.59
Diluted Earnings Per Share	$0.51	$3.70	$0.59
COMMON SHARES
Basic Shares Outstanding	40.00M shares	40.19M shares	41.81M shares
Diluted Shares Outstanding

Balance Sheet

Concept	2019 Q4	2019	2018 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$402.1M	$402.1M	$387.6M
YoY Change	3.74%	3.74%	8.82%
Cash & Equivalents	$367.3M	$367.3M	$326.8M
Short-Term Investments	$34.70M	$34.70M	$60.80M
Other Short-Term Assets	$43.49M	$103.2M	$27.72M
YoY Change	56.9%	31.8%	2.7%
Inventory
Prepaid Expenses
Receivables	$12.73M	$118.6M	$10.02M
Other Receivables	$350.9M	$350.9M	$300.8M
Total Short-Term Assets	$974.7M	$974.7M	$866.5M
YoY Change	12.49%	12.49%	11.25%
LONG-TERM ASSETS
Property, Plant & Equipment	$147.7M	$204.6M	$117.2M
YoY Change	26.02%	74.57%	22.53%
Goodwill	$12.70M		$12.69M
YoY Change	0.11%		0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$5.975M	$202.9M	$4.851M
YoY Change	23.17%	3.89%	37.0%
Total Long-Term Assets	$420.3M	$420.3M	$325.3M
YoY Change	29.2%	29.2%	14.23%
TOTAL ASSETS
Total Short-Term Assets	$974.7M	$974.7M	$866.5M
Total Long-Term Assets	$420.3M	$420.3M	$325.3M
Total Assets	$1.395B	$1.395B	$1.192B
YoY Change	17.05%	17.05%	12.04%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$4.565M	$4.600M	$10.62M
YoY Change	-57.02%	-56.6%	64.76%
Accrued Expenses	$58.71M	$864.5M	$28.89M
YoY Change	103.23%	13.5%	11.16%
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	$869.0M	$869.0M	$772.3M
YoY Change	12.52%	12.52%	6.57%
LONG-TERM LIABILITIES
Long-Term Debt	$269.4M	$269.4M	$144.4M
YoY Change	86.57%	86.57%	38.31%
Other Long-Term Liabilities	$0.00	$252.5M	$9.996M
YoY Change	-100.0%	27.91%	470.55%
Total Long-Term Liabilities	$521.9M	$521.9M	$341.8M
YoY Change	52.68%	52.69%	25.37%
TOTAL LIABILITIES
Total Short-Term Liabilities	$869.0M	$869.0M	$772.3M
Total Long-Term Liabilities	$521.9M	$521.9M	$341.8M
Total Liabilities	$1.391B	$1.391B	$1.114B
YoY Change	24.84%	24.85%	11.71%
SHAREHOLDERS EQUITY
Retained Earnings	$499.5M		$397.9M
YoY Change	25.51%		34.08%
Common Stock	$48.70M		$37.31M
YoY Change	30.53%		44.09%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$544.1M		$357.6M
YoY Change	52.17%		39.48%
Treasury Stock Shares	16.12M shares		14.56M shares
Shareholders Equity	$4.079M	$4.100M	$77.68M
YoY Change
Total Liabilities & Shareholders Equity	$1.395B	$1.395B	$1.192B
YoY Change	17.05%	17.05%	12.04%

Cashflow Statement

Concept	2019 Q4	2019	2018 Q4
OPERATING ACTIVITIES
Net Income	$20.40M	$151.1M	$24.66M
YoY Change	-17.28%	11.58%	58.51%
Depreciation, Depletion And Amortization	$7.800M	$28.72M	$6.500M
YoY Change	20.0%	25.75%	35.42%
Cash From Operating Activities	$158.1M	$205.2M	$114.2M
YoY Change	38.44%	11.21%	-21.13%
INVESTING ACTIVITIES
Capital Expenditures	-$20.30M	$56.31M	-$13.80M
YoY Change	47.1%	59.38%	102.94%
Acquisitions
YoY Change
Other Investing Activities	$26.20M	$26.60M	-$23.00M
YoY Change	-213.91%	-145.24%	-7766.67%
Cash From Investing Activities	$5.900M	-$29.72M	-$36.80M
YoY Change	-116.03%	-68.43%	457.58%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-30.20M	-$118.4M	-64.70M
YoY Change	-53.32%	13.28%	9.48%
NET CHANGE
Cash From Operating Activities	158.1M	$205.2M	114.2M
Cash From Investing Activities	5.900M	-$29.72M	-36.80M
Cash From Financing Activities	-30.20M	-$118.4M	-64.70M
Net Change In Cash	133.8M	$57.08M	12.70M
YoY Change	953.54%	-503.71%	-83.94%
FREE CASH FLOW
Cash From Operating Activities	$158.1M	$205.2M	$114.2M
Capital Expenditures	-$20.30M	$56.31M	-$13.80M
Free Cash Flow	$178.4M	$148.8M	$128.0M
YoY Change	39.38%	-0.21%	-15.57%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019	dei	Amendment Flag AmendmentFlag	false
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CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Document Period End Date DocumentPeriodEndDate	2019-12-31
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0001000753
CY2019	dei	Entity Registrant Name EntityRegistrantName	INSPERITY, INC.
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	34716000	USD
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CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	120000000	shares
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CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	55489000	shares
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CY2019	dei	Local Phone Number LocalPhoneNumber	358-8986
CY2019	dei	Security12b Title Security12bTitle	Common Stock, Par value $0.01 per share
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CY2019Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2018Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2018Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	14555000	shares
CY2019Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	16117000	shares
CY2019	dei	Document Type DocumentType	10-K
CY2019	dei	Document Annual Report DocumentAnnualReport	true
CY2019	dei	Document Transition Report DocumentTransitionReport	false
CY2019	dei	Entity File Number EntityFileNumber	1-13998
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	76-0479645
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	19001 Crescent Springs Drive
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Kingwood,
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	TX
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	77339
CY2019	dei	City Area Code CityAreaCode	281
CY2019	dei	Trading Symbol TradingSymbol	NSP
CY2019	dei	Security Exchange Name SecurityExchangeName	NYSE
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CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.24
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.02
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.70
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.22
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.01
CY2019	nsp	Gross Billings GrossBillings	27212010000	USD
CY2018	nsp	Gross Billings GrossBillings	23830731000	USD
CY2017	nsp	Gross Billings GrossBillings	20173812000	USD
CY2019	nsp	Worksite Employee Payroll Cost WorksiteEmployeePayrollCost	22897206000	USD
CY2018	nsp	Worksite Employee Payroll Cost WorksiteEmployeePayrollCost	20002182000	USD
CY2017	nsp	Worksite Employee Payroll Cost WorksiteEmployeePayrollCost	16873589000	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
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3300223000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	151099000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	135413000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	84402000	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
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-2000	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
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	84400000	USD
CY2016Q4	us-gaap	Stockholders Equity StockholdersEquity	60525000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	38735000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	24345000	USD
CY2017	us-gaap	Stockholders Equity Other StockholdersEquityOther	-1554000	USD
CY2017	us-gaap	Dividends Common Stock DividendsCommonStock	65768000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-2000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	84402000	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
CY2019	us-gaap	Net Income Loss NetIncomeLoss	151099000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	135413000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	3023000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2005000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	84402000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	28723000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	22842000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	18182000	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
CY2017	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	-80000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	23993000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	20425000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	24345000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	4860000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4533000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	9742000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	65156000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	66642000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	63697000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	2007000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-2371000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-4259000	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
CY2017	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	7465000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2496000	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
CY2017	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	2258000	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
CY2017	us-gaap	Increase Decrease In Other Employee Related Liabilities IncreaseDecreaseInOtherEmployeeRelatedLiabilities	55481000	USD
CY2019	nsp	Increase Decreasein Wse Epayrollexpense IncreaseDecreaseinWSEEpayrollexpense	71880000	USD
CY2018	nsp	Increase Decreasein Wse Epayrollexpense IncreaseDecreaseinWSEEpayrollexpense	62577000	USD
CY2017	nsp	Increase Decreasein Wse Epayrollexpense IncreaseDecreaseinWSEEpayrollexpense	52188000	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
CY2017	us-gaap	Increase Decrease In Health Care Insurance Liabilities IncreaseDecreaseInHealthCareInsuranceLiabilities	-285000	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
CY2017	us-gaap	Increase Decrease In Workers Compensation Liabilities IncreaseDecreaseInWorkersCompensationLiabilities	23945000	USD
CY2019	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	6359000	USD
CY2018	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	8941000	USD
CY2017	us-gaap	Increase Decrease In Accrued Salaries IncreaseDecreaseInAccruedSalaries	17138000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-4616000	USD
CY2018	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	10749000	USD
CY2017	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-4875000	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
CY2017	us-gaap	Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities	128800000	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
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	213202000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	110131000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	87887000	USD
CY2017	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	1752000	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
CY2017	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	1561000	USD
CY2019	nsp	Marketable Securities Proceeds From Dispositions MarketableSecuritiesProceedsFromDispositions	28313000	USD
CY2018	nsp	Marketable Securities Proceeds From Dispositions MarketableSecuritiesProceedsFromDispositions	16299000	USD
CY2017	nsp	Marketable Securities Proceeds From Dispositions MarketableSecuritiesProceedsFromDispositions	0	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
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	33337000	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
CY2017	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	278000	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
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-33250000	USD
CY2019	nsp	Treasury Stock Acquired TreasuryStockAcquired	203043000	USD
CY2018	nsp	Treasury Stock Acquired TreasuryStockAcquired	113327000	USD
CY2017	nsp	Treasury Stock Acquired TreasuryStockAcquired	38735000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	48622000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	33408000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	65768000	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
CY2017	us-gaap	Proceeds From Secured Lines Of Credit ProceedsFromSecuredLinesOfCredit	0	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
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	1554000	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
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-102949000	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
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	77003000	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
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	472609000	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
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
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	286034000	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
CY2016Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	42637000	USD
CY2018Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	166474000	USD
CY2017Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	154215000	USD
CY2016Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	143938000	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
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	472609000	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
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	38299000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	40730000	USD
CY2019	nsp	Workers Compensation Expense WorkersCompensationExpense	63538000	USD
CY2018	nsp	Workers Compensation Expense WorkersCompensationExpense	72066000	USD
CY2019	nsp	Workers Compensation Discount Changed During Period WorkersCompensationDiscountChangedDuringPeriod	4629000	USD
CY2018	nsp	Workers Compensation Discount Changed During Period WorkersCompensationDiscountChangedDuringPeriod	7829000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	40872000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	7421000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	4006000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	3257000	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
CY2017	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	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
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	3300223000	USD
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:120%;padding-bottom:13px;padding-top:13px;text-align:justify;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#4c8c2b;font-style:italic;font-weight:bold;text-decoration:none;">Use of Estimates</span></div><div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;text-indent:0px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">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>
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="line-height:120%;padding-bottom:13px;padding-top:13px;text-align:justify;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#4c8c2b;font-style:italic;font-weight:bold;text-decoration:none;">Concentrations of Credit Risk</span></div><div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;text-indent:0px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Financial instruments that could potentially subject us to concentration of credit risk include accounts receivable and marketable securities.</span></div>
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	403301000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	350808000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	255595000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	233595000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	147706000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	117213000	USD
CY2019	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	7800000	USD
CY2018	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	6000000.0	USD
CY2017	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	4100000	USD
CY2019Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	25800000	USD
CY2018Q4	us-gaap	Capitalized Computer Software Net CapitalizedComputerSoftwareNet	19600000	USD
CY2019	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;text-indent:0px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">The following table provides the activity and balances related to incurred but not paid workers’ compensation claims:</span></div><div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;width:98.36065573770492%;border-collapse:collapse;text-align:left;"><tr><td colspan="7"/></tr><tr><td style="width:74%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="6" style="vertical-align:bottom;border-bottom:1px solid #4c8c2b;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:center;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#4c8c2b;font-weight:bold;">Year Ended December 31,</span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:1px solid #4c8c2b;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:9pt;"><span style="font-family:Arial;font-size:9pt;color:#4c8c2b;font-style:italic;">(in thousands)</span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #4c8c2b;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#4c8c2b;font-weight:bold;">2019</span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #4c8c2b;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#4c8c2b;font-weight:bold;">2018</span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:8px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:8px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:8px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Beginning balance</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>229,639</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>207,630</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Accrued claims</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>63,538</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>72,066</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Present value discount</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>(4,629</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">)</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>(7,829</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">)</span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Paid claims</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>(45,644</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">)</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>(42,228</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">)</span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Ending balance</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;"><span>242,904</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;"><span>229,639</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:18px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:18px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:18px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Current portion of accrued claims</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>49,295</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>42,227</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Long-term portion of accrued claims</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>193,609</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;"><span>187,412</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">Total accrued claims</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;"><span>242,904</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;font-weight:bold;"><span>229,639</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr></table></div><span style="font-family:Arial;font-size:10pt;"><br/></span></div>
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	50800000	USD
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	63700000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019Q4	us-gaap	Goodwill Gross GoodwillGross	21200000	USD
CY2019Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	8500000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	12700000	USD
CY2019Q4	nsp	Percentageofourhealthinsurancecoverageprovidedby United PercentageofourhealthinsurancecoverageprovidedbyUnited	0.87
CY2019	nsp	Number Of Days In Advance Of Beginning Of Reporting Quarter Carrier Establishes Cash Funding Rates NumberOfDaysInAdvanceOfBeginningOfReportingQuarterCarrierEstablishesCashFundingRates	P90D
CY2019Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000.0	USD
CY2019Q4	nsp	Required Deposit For Health Care Costs RequiredDepositForHealthCareCosts	6500000	USD
CY2019Q4	nsp	Prepaid Health Insurance Current And Noncurrent PrepaidHealthInsuranceCurrentAndNoncurrent	2600000	USD
CY2019Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000.0	USD
CY2019Q4	nsp	Portionofinsurancecoststhatislessthantheagreeduponsurplusincludedinaccruedhealthinsurancecostsacntliab Portionofinsurancecoststhatislessthantheagreeduponsurplusincludedinaccruedhealthinsurancecostsacntliab	-6400000	USD
CY2019Q4	nsp	Premiums Owed To United PremiumsOwedToUnited	9300000	USD
CY2019Q4	nsp	Benefits Costs Incurred Relatedto Runoff BenefitsCostsIncurredRelatedtoRunoff	2300000	USD
CY2018Q4	nsp	Benefits Costs Incurred Relatedto Runoff BenefitsCostsIncurredRelatedtoRunoff	-1300000	USD
CY2017Q4	nsp	Benefits Costs Incurred Relatedto Runoff BenefitsCostsIncurredRelatedtoRunoff	1200000	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
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
CY2017	nsp	Decrease Increase In Accrued Workers Compensation Costs For Changes In Estimated Losses DecreaseIncreaseInAccruedWorkersCompensationCostsForChangesInEstimatedLosses	16300000	USD
CY2019	nsp	Us Treasury Rates That Correspond With Weighted Average Estimated Claim Payout Period USTreasuryRatesThatCorrespondWithWeightedAverageEstimatedClaimPayoutPeriod	0.019
CY2018	nsp	Us Treasury Rates That Correspond With Weighted Average Estimated Claim Payout Period USTreasuryRatesThatCorrespondWithWeightedAverageEstimatedClaimPayoutPeriod	0.026
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Opening Balance Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseOpeningBalanceAdjustments	229639000	USD
CY2017Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Opening Balance Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseOpeningBalanceAdjustments	207630000	USD
CY2019	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	45644000	USD
CY2018	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	42228000	USD
CY2019Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	242904000	USD
CY2018Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	229639000	USD
CY2019Q4	nsp	Workers Compensation Liability Current Net WorkersCompensationLiabilityCurrentNet	49295000	USD
CY2018Q4	nsp	Workers Compensation Liability Current Net WorkersCompensationLiabilityCurrentNet	42227000	USD
CY2019Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	193609000	USD
CY2018Q4	us-gaap	Workers Compensation Liability Noncurrent WorkersCompensationLiabilityNoncurrent	187412000	USD
CY2019Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	242904000	USD
CY2018Q4	us-gaap	Workers Compensation Liability Current And Noncurrent WorkersCompensationLiabilityCurrentAndNoncurrent	229639000	USD
CY2019Q4	nsp	Workers Compensation Administrative Fees Accrued WorkersCompensationAdministrativeFeesAccrued	3600000	USD
CY2018Q4	nsp	Workers Compensation Administrative Fees Accrued WorkersCompensationAdministrativeFeesAccrued	3600000	USD
CY2019	nsp	Undiscounted Accrued Workers Compensation Costs UndiscountedAccruedWorkersCompensationCosts	262900000	USD
CY2018	nsp	Undiscounted Accrued Workers Compensation Costs UndiscountedAccruedWorkersCompensationCosts	247400000	USD
CY2019	nsp	Time Period Incurred Claims Expected To Be Paid Recorded As Restricted Cash TimePeriodIncurredClaimsExpectedToBePaidRecordedAsRestrictedCash	P1Y
CY2019	nsp	Return Of Excess Claim Funds ReturnOfExcessClaimFunds	18800000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	49300000	USD
CY2019Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	175900000	USD
CY2019	nsp	Time Period Estimate Of Incurred Claim Costs To Be Paid Included In Short Term Liabilities TimePeriodEstimateOfIncurredClaimCostsToBePaidIncludedInShortTermLiabilities	P1Y
CY2019Q4	nsp	Number Of Stock Based Employee Compensation Plans NumberOfStockBasedEmployeeCompensationPlans	1
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P3Y
CY2019	nsp	Percentageofgrantsissuedtodirectorsthatarevestedforannualawardgrants. Percentageofgrantsissuedtodirectorsthatarevestedforannualawardgrants.	1
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P3Y
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P3Y
CY2019	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="line-height:120%;padding-bottom:13px;padding-top:13px;text-align:justify;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#4c8c2b;font-style:italic;font-weight:bold;text-decoration:none;">Reclassifications</span></div><div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;text-indent:0px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">Certain immaterial prior year amounts have been reclassified to conform to the </span><span style="font-family:Arial;font-size:10pt;color:#000000;text-decoration:none;">2019</span><span style="font-family:Arial;font-size:10pt;"> presentation.</span></div>
CY2019	us-gaap	Description Of New Accounting Pronouncements Not Yet Adopted DescriptionOfNewAccountingPronouncementsNotYetAdopted	<div style="line-height:120%;padding-bottom:13px;padding-top:13px;text-align:justify;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;color:#4c8c2b;font-style:italic;font-weight:bold;text-decoration:none;">New Accounting Pronouncements</span></div><div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;text-indent:0px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">In June 2016, the FASB issued ASU 2016-13, </span><span style="font-family:Arial;font-size:10pt;font-style:italic;">Financial Instruments - Credit Losses. </span><span style="font-family:Arial;font-size:10pt;">The new standard defines a current expected credit loss model which requires us to measure all expected credit loss for financial instruments held at the reporting date based on historical experience, current conditions and reasonable forecasts. This replaced the existing incurred loss model and is applicable to the measurement of credit losses on financial assets, including trade receivables. The guidance is effective for interim periods and fiscal years beginning after December 15, 2019. </span><span style="font-family:Arial;font-size:10pt;">We </span><span style="font-family:Arial;font-size:10pt;">do not expect the new standard to have a material </span><span style="font-family:Arial;font-size:10pt;">impact on our consolidated financial statements.</span></div><div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;text-indent:0px;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">In August 2018, the FASB issued ASU 2018-15, </span><span style="font-family:Arial;font-size:10pt;font-style:italic;">Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. </span><span style="font-family:Arial;font-size:10pt;">The new standard requires a customer in a cloud computing arrangement that is a service contract to follow the </span></div><div style="line-height:120%;padding-bottom:13px;padding-top:0px;text-align:left;font-size:10pt;"><span style="font-family:Arial;font-size:10pt;">internal-use software guidance in ASC 350-40 to determine which implementation costs to capitalize as assets. The guidance is effective for fiscal years beginning after December 15, 2019. We </span><span style="font-family:Arial;font-size:10pt;">do not expect the new standard to have a material </span><span style="font-family:Arial;font-size:10pt;">impact on our consolidated financial statements.</span></div>
CY2019Q4	nsp	Money Market Funds Overnight Holdings At Carrying Value MoneyMarketFundsOvernightHoldingsAtCarryingValue	349857000	USD
CY2018Q4	nsp	Money Market Funds Overnight Holdings At Carrying Value MoneyMarketFundsOvernightHoldingsAtCarryingValue	311158000	USD
CY2019Q4	us-gaap	Short Term Investments ShortTermInvestments	47946000	USD
CY2018Q4	us-gaap	Short Term Investments ShortTermInvestments	77492000	USD
CY2019Q4	us-gaap	Cash Cash	36521000	USD
CY2018Q4	us-gaap	Cash Cash	33207000	USD
CY2019Q4	us-gaap	Drafts Payable DraftsPayable	32254000	USD
CY2018Q4	us-gaap	Drafts Payable DraftsPayable	34303000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents And Short Term Investments CashCashEquivalentsAndShortTermInvestments	402070000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents And Short Term Investments CashCashEquivalentsAndShortTermInvestments	387554000	USD
CY2019Q4	nsp	Payroll Withholdings Included In Cash Balance PayrollWithholdingsIncludedInCashBalance	234600000	USD
CY2018Q4	nsp	Payroll Withholdings Included In Cash Balance PayrollWithholdingsIncludedInCashBalance	224500000	USD
CY2019Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	59600000	USD
CY2018Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	34200000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	363075000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	325819000	USD
CY2019Q4	us-gaap	Us Government Securities At Carrying Value USGovernmentSecuritiesAtCarryingValue	34728000	USD
CY2018Q4	us-gaap	Us Government Securities At Carrying Value USGovernmentSecuritiesAtCarryingValue	52197000	USD
CY2019Q4	us-gaap	Investments Fair Value Disclosure InvestmentsFairValueDisclosure	0	USD
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CY2019Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	397803000	USD
CY2018Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	388650000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	12731000	USD
CY2018Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	10015000	USD
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CY2018Q4	nsp	Unbilled Unbilled	385567000	USD
CY2019Q4	us-gaap	Other Receivables OtherReceivables	4960000	USD
CY2018Q4	us-gaap	Other Receivables OtherReceivables	5041000	USD
CY2019Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	465779000	USD
CY2018Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	400623000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	900000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1000000.0	USD
CY2019	nsp	Accounts Receivable Due Date Prior To Applicable Payroll Date AccountsReceivableDueDatePriorToApplicablePayrollDate	P1D
CY2019Q4	nsp	Unbilled Accrued Worksite Employee Payroll Costs UnbilledAccruedWorksiteEmployeePayrollCosts	401859000	USD
CY2018Q4	nsp	Unbilled Accrued Worksite Employee Payroll Costs UnbilledAccruedWorksiteEmployeePayrollCosts	329979000	USD
CY2019Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	105841000	USD
CY2018Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	89765000	USD
CY2019Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	59612000	USD
CY2018Q4	nsp	Client Prepayments Included In Cash Balance ClientPrepaymentsIncludedInCashBalance	34177000	USD
CY2019Q4	nsp	Unbilled Unbilled	448088000	USD
CY2018Q4	nsp	Unbilled Unbilled	385567000	USD
CY2018Q4	nsp	Depositsandprepaidhealthinsurance Depositsandprepaidhealthinsurance	181674000	USD
CY2019Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000.0	USD
CY2019Q3	us-gaap	Line Of Credit Facility Current Borrowing Capacity LineOfCreditFacilityCurrentBorrowingCapacity	350000000	USD
CY2019Q4	us-gaap	Line Of Credit Facility Current Borrowing Capacity LineOfCreditFacilityCurrentBorrowingCapacity	500000000	USD
CY2019Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000	USD
CY2018Q4	nsp	Prepaid Health Insurance PrepaidHealthInsurance	9000000	USD
CY2019Q4	nsp	Deposits Health Insurance DepositsHealthInsurance	8100000	USD
CY2018Q4	nsp	Deposits Health Insurance DepositsHealthInsurance	6200000	USD
CY2019Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	175913000	USD
CY2018Q4	nsp	Deposits Workers Compensation DepositsWorkersCompensation	166474000	USD
CY2019Q4	nsp	Depositsandprepaidhealthinsurance Depositsandprepaidhealthinsurance	193013000	USD
CY2019Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	550000000	USD
CY2019	nsp	Percentage Of Subsidiary Stock Securing Debt PercentageOfSubsidiaryStockSecuringDebt	0.65
CY2019Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	1000000.0	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	269400000	USD
CY2019Q4	us-gaap	Long Term Debt Maturity Date LongTermDebtMaturityDate	2024-09-13
CY2019Q4	nsp	Applicable Margin Federal Funds Rate ApplicableMarginFederalFundsRate	0.0050
CY2019Q4	nsp	Applicable Margin30 Day Libor ApplicableMargin30DayLibor	0.0200
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CY2019	us-gaap	Debt Instrument Interest Rate During Period DebtInstrumentInterestRateDuringPeriod	0.038
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	4252000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	3306000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	4564000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	3918000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Software DeferredTaxLiabilitiesDeferredExpenseCapitalizedSoftware	6475000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Capitalized Software DeferredTaxLiabilitiesDeferredExpenseCapitalizedSoftware	4950000	USD
CY2019Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	39360000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	21464000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	3956000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	8816000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	3209000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	0	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	15949000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	0	USD
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CY2018Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	474000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	35404000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	12648000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	5946000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	8612000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	632000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	709000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Self Insurance DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance	5404000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Self Insurance DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsSelfInsurance	4739000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	1223000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	918000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	6712000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	6183000	USD
CY2019Q4	nsp	Deferred Tax Assets Operating Lease Liablities DeferredTaxAssetsOperatingLeaseLiablities	19158000	USD
CY2018Q4	nsp	Deferred Tax Assets Operating Lease Liablities DeferredTaxAssetsOperatingLeaseLiablities	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	673000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	676000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	287000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	305000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	40035000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	22142000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	675000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	678000	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	4831000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	27385000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	40347000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	30009000	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
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	5988000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	33684000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	51480000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	35997000	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
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CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1135000	USD
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CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	4860000	USD
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CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	38544000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	46947000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	45739000	USD
CY2019	us-gaap	New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification	14600000	USD
CY2018	us-gaap	New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification	3900000	USD
CY2017	us-gaap	New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification	6800000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	39825000	USD
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CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	45549000	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
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	4085000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	5959000	USD
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CY2017	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	2649000	USD
CY2018	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1066409	shares
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CY2019Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	413833	shares
CY2019Q4	us-gaap	Liability For Uncertain Tax Positions Current LiabilityForUncertainTaxPositionsCurrent	0	USD
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CY2019	us-gaap	Shares Paid For Tax Withholding For Share Based Compensation SharesPaidForTaxWithholdingForShareBasedCompensation	227208	shares
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CY2018	us-gaap	Income Tax Reconciliation Deductions Qualified Production Activities IncomeTaxReconciliationDeductionsQualifiedProductionActivities	0	USD
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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
CY2017	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-6218000	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
CY2017	us-gaap	Income Tax Reconciliation Tax Credits Research IncomeTaxReconciliationTaxCreditsResearch	634000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	0	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	0	USD
CY2017	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	669000	USD
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CY2018	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2017	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	2559000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	128000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-247000	USD
CY2017	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-707000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	38544000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	46947000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	45739000	USD
CY2019Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2018Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.20
CY2019Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2018Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.20
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2018Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.20
CY2018	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	1875000	USD
CY2017	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	1517000	USD
CY2018Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.20
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	48600000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	33400000	USD
CY2019Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	20000000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	2615253	shares
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	24000000.0	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	20400000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	24300000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Accelerated Compensation Cost ShareBasedCompensationArrangementByShareBasedPaymentAwardAcceleratedCompensationCost	2300000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4900000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5300000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8500000	USD
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
CY2017	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	38000	shares
CY2019	us-gaap	Net Income Loss NetIncomeLoss	151099000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	135413000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	84402000	USD
CY2019	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	1759000	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
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	82885000	USD
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
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	41067000	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
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2017	nsp	Incremental Shares From Assumed Conversions Of Common Stock Options IncrementalSharesFromAssumedConversionsOfCommonStockOptions	204000	shares
CY2019	nsp	Adjusted Weighted Average Common Shares Outstanding AdjustedWeightedAverageCommonSharesOutstanding	40352000	shares
CY2018	nsp	Adjusted Weighted Average Common Shares Outstanding AdjustedWeightedAverageCommonSharesOutstanding	41506000	shares
CY2017	nsp	Adjusted Weighted Average Common Shares Outstanding AdjustedWeightedAverageCommonSharesOutstanding	41271000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2017	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2019	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	15900000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	15400000	USD
CY2017	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	15400000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	17100000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	56886000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	15143000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	58863000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	74006000	USD
CY2019Q4	nsp	Landlordfundedtenantimprovements Landlordfundedtenantimprovements	12397000	USD
CY2019Q4	us-gaap	Deferred Rent Credit Noncurrent DeferredRentCreditNoncurrent	4723000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	56886000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.045
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	18087000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	15611000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	14206000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	11682000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	8952000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	15758000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	84296000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	10290000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	74006000	USD
CY2019Q4	us-gaap	Lessor Operating Lease Lease Not Yet Commenced Assumption And Judgment Value Of Underlying Asset Amount LessorOperatingLeaseLeaseNotYetCommencedAssumptionAndJudgmentValueOfUnderlyingAssetAmount	16100000	USD
CY2019Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	79562000	USD
CY2019Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	16994000	USD
CY2019Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary	8234000	USD
CY2019Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary	3188000	USD
CY2019Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fifth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary	1295000	USD
CY2019Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	678000	USD
CY2019Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance Sheet Amount UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount	109951000	USD
CY2019	us-gaap	Loss Contingency Damages Sought Value LossContingencyDamagesSoughtValue	146000000.0	USD
CY2019Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1153010000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1043316000	USD
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1043388000	USD
CY2019Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1075090000	USD
CY2019Q1	us-gaap	Gross Profit GrossProfit	226717000	USD
CY2019Q2	us-gaap	Gross Profit GrossProfit	173735000	USD
CY2019Q3	us-gaap	Gross Profit GrossProfit	170546000	USD
CY2019Q4	us-gaap	Gross Profit GrossProfit	161936000	USD
CY2019Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	85461000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	38720000	USD
CY2019Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	34733000	USD
CY2019Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	27719000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	76289000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	28556000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	25859000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	20395000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.86
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.69
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.64
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.51
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.85
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.69
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.63
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.51
CY2018Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1014372000	USD
CY2018Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	922295000	USD
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	925126000	USD
CY2018Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	966756000	USD
CY2018Q1	us-gaap	Gross Profit GrossProfit	199720000	USD
CY2018Q2	us-gaap	Gross Profit GrossProfit	154544000	USD
CY2018Q3	us-gaap	Gross Profit GrossProfit	166054000	USD
CY2018Q4	us-gaap	Gross Profit GrossProfit	161591000	USD
CY2018Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	64703000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	33581000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	48133000	USD
CY2018Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	32619000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	49991000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	24560000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	36207000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	24655000	USD
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.20
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.86
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.59
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.18
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.58
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.86
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.59

Files In Submission

Name	View Source	Status
0001000753-20-000013-index-headers.html	Edgar Link	pending
0001000753-20-000013-index.html	Edgar Link	pending
0001000753-20-000013.txt	Edgar Link	pending
0001000753-20-000013-xbrl.zip	Edgar Link	pending
a12312019-documentx10k.htm	Edgar Link	pending
a12312019-documentx10k_htm.xml	Edgar Link	completed
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a12312019nsp-ex1019l18.htm	Edgar Link	pending
a12312019nsp-ex1020ees.htm	Edgar Link	pending
a12312019nsp-ex1022ltip.htm	Edgar Link	pending
a12312019nsp-ex1034.htm	Edgar Link	pending
a12312019nsp-ex211xsub.htm	Edgar Link	pending
a12312019nsp-ex231xcon.htm	Edgar Link	pending
a12312019nsp-ex241xpoas.htm	Edgar Link	pending
a12312019nsp-ex311.htm	Edgar Link	pending
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chart-a72de5cba01deed3037.jpg	Edgar Link	pending
chart-c8ba88fd864668087da.jpg	Edgar Link	pending
chart-e73a4c6acdb8774dcdd.jpg	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
insperitylogoa06.jpg	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
nsp-20191231.xsd	Edgar Link	pending
nsp-20191231_cal.xml	Edgar Link	unprocessable
nsp-20191231_def.xml	Edgar Link	unprocessable
nsp-20191231_lab.xml	Edgar Link	unprocessable
nsp-20191231_pre.xml	Edgar Link	unprocessable
nsp201910kimage1a03.jpg	Edgar Link	pending
nsp201910kimage2a01.jpg	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$NSP
INSPERITY, INC. Stock $nsp

2019 Q4 Form 10-K Financial Statement

#000100075320000013 Filed on February 12, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NSP INSPERITY, INC. Stock $nsp

2019 Q4 Form 10-K Financial Statement

#000100075320000013 Filed on February 12, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NSP
INSPERITY, INC. Stock $nsp