Quarterly report pursuant to Section 13 or 15(d)

Funds Held for Clients and Corporate Investments (Details)

v2.4.1.9
Funds Held for Clients and Corporate Investments (Details) (USD $)
In Millions, unless otherwise specified
Feb. 28, 2015
May 31, 2014
Type of issue:    
Funds held for clients money market securities and other cash equivalents, Amortized cost $ 2,657.9payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsAmortizedCost $ 1,579.2payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsAmortizedCost
Funds held for clients money market securities and other cash equivalents, Gross unrealized gains 0payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsGrossUnrealizedGains 0payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsGrossUnrealizedGains
Funds held for clients money market securities and other cash equivalents, Gross unrealized losses 0payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsGrossUnrealizedLosses 0payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsGrossUnrealizedLosses
Funds held for clients money market securities and other cash equivalents, Fair value 2,657.9payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsFairValue 1,579.2payx_FundsHeldForClientsMoneyMarketSecuritiesAndOtherCashEquivalentsFairValue
Available-for-sale securities:    
Amortized cost 3,147.5us-gaap_AvailableForSaleSecuritiesAmortizedCost 3,356.9us-gaap_AvailableForSaleSecuritiesAmortizedCost
Gross unrealized gains 36.8payx_AvailableForSaleSecuritiesGrossUnrealizedGains1 37.5payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
Gross unreailzed losses (1.2)payx_AvailableForSaleSecuritiesGrossUnrealizedLosses (3.0)payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
Fair value 3,183.1us-gaap_AvailableForSaleSecurities 3,391.4us-gaap_AvailableForSaleSecurities
Other, Amortized cost 12.4payx_OtherSecuritiesAmortizedCost 10.6payx_OtherSecuritiesAmortizedCost
Other, Gross unrealized gains 1.5payx_OtherSecuritiesGrossUnrealizedGains 1.7payx_OtherSecuritiesGrossUnrealizedGains
Other, Gross unrealized losses 0payx_OtherSecuritiesGrossUnrealizedLosses 0payx_OtherSecuritiesGrossUnrealizedLosses
Other, Fair value 13.9payx_OtherSecuritiesFairValue 12.3payx_OtherSecuritiesFairValue
Total funds held for clients and corporate investments, Amortized cost 5,817.8payx_FundsHeldForClientsAndCorporateInvestmentsAmortizedCost 4,946.7payx_FundsHeldForClientsAndCorporateInvestmentsAmortizedCost
Total funds held for clients and corporate investments, Gross unrealized gains 38.3payx_FundsHeldForClientsAndCorporateInvestmentsGrossUnrealizedGains 39.2payx_FundsHeldForClientsAndCorporateInvestmentsGrossUnrealizedGains
Total funds held for clients and corporate investments, Gross unrealized losses (1.2)payx_FundsHeldForClientsAndCorporateInvestmentsGrossUnrealizedLosses (3.0)payx_FundsHeldForClientsAndCorporateInvestmentsGrossUnrealizedLosses
Total funds held for clients and corporate investments, Fair value 5,854.9payx_FundsHeldForClientsAndCorporateInvestmentsFairValue 4,982.9payx_FundsHeldForClientsAndCorporateInvestmentsFairValue
General obligation municipal bonds [Member]    
Available-for-sale securities:    
Amortized cost 1,689.5us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember 		1,605.4us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember
Gross unrealized gains 23.6payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember 		25.0payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember
Gross unreailzed losses (0.8)payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember 		(1.9)payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember
Fair value 1,712.3us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember 		1,628.5us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_GeneralObligationMunicipalBondsMember
Pre-refunded municipal bonds [Member]    
Available-for-sale securities:    
Amortized cost 103.5us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1] 140.4us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1]
Gross unrealized gains 1.7payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1] 2.4payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1]
Gross unreailzed losses 0payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1] 0payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1]
Fair value 105.2us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1] 142.8us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_PreRefundedMunicipalBondsMember 		[1]
Revenue municipal bonds [Member]    
Available-for-sale securities:    
Amortized cost 969.6us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember 		858.8us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember
Gross unrealized gains 11.5payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember 		10.1payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember
Gross unreailzed losses (0.4)payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember 		(1.1)payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember
Fair value 980.7us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember 		867.8us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= payx_RevenueMunicipalBondsMember
Variable rate demand notes [Member]    
Available-for-sale securities:    
Amortized cost 384.9us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember 		752.3us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember
Gross unrealized gains 0payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember 		0payx_AvailableForSaleSecuritiesGrossUnrealizedGains1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember
Gross unreailzed losses 0payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember 		0payx_AvailableForSaleSecuritiesGrossUnrealizedLosses
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember
Fair value $ 384.9us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember 		$ 752.3us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_VariableRateDemandObligationMember
[1] Pre-refunded municipal bonds are secured by an escrow fund of U.S. government obligations.