v2.4.1.9
Income Taxes - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Income Taxes [Line Items]      
Change in uncertain tax positions $ 1.1us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions $ 1.8us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions $ 28.5us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions
Cash paid for income taxes, net of refunds 105.4us-gaap_ProceedsFromIncomeTaxRefunds 99.5us-gaap_ProceedsFromIncomeTaxRefunds 38.4us-gaap_ProceedsFromIncomeTaxRefunds
Decrease in deferred tax liability 27.1us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAdjustmentOfDeferredTaxAssetLiability    
Accrued interest and penalties 0.3us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued 0.9us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued  
Valuation Allowance, Operating Loss Carryforwards [Member]      
Income Taxes [Line Items]      
Decrease in valuation allowance 37.6us-gaap_ValuationAllowancesAndReservesAdjustments
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_ValuationAllowanceOperatingLossCarryforwardsMember
   
Fibra Prologis [Member]      
Income Taxes [Line Items]      
Decrease in deferred tax liability $ 62.8us-gaap_IncomeTaxExpenseBenefitContinuingOperationsAdjustmentOfDeferredTaxAssetLiability
/ us-gaap_BusinessAcquisitionAxis
= pld_FibraPrologisMember