2.2.0.25truefalse06151 - Disclosure - Fair Value Measurement (Details 1)truefalseIn Millionsfalse1falsefalseUSDtruefalse{us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityTypeAxis} : Contingent consideration obligation [member] 1/1/2010 - 12/31/2010 USD ($) $TwelveMonthsEnded_31Dec2010_Contingent_Consideration_Obligation_Memberhttp://www.sec.gov/CIK0000884629duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseContingent consideration obligation [member]us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityTypeAxisxbrldihttp://xbrl.org/2006/xbrldiwpi_ContingentConsiderationObligationMemberus-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2falsefalseUSDtruefalse{us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityTypeAxis} : Contingent consideration obligation [member] 1/1/2009 - 12/31/2009 USD ($) $TwelveMonthsEnded_31Dec2009_Contingent_Consideration_Obligation_Memberhttp://www.sec.gov/CIK0000884629duration2009-01-01T00:00:002009-12-31T00:00:00falsefalseContingent consideration obligation [member]us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityTypeAxisxbrldihttp://xbrl.org/2006/xbrldiwpi_ContingentConsiderationObligationMemberus-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2true0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForwardus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringA roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.falsefalseSummary of the changes in financial liabilities measured at fair value on a recurring basis using significant unobservable inputs3false0wpi_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValuewpifalsecreditinstantFair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value.falsefalsefalsefalsefalsefalsefalsetruefalsefalseperiodstartlabel1truefalsefalse111000000111.0falsetruefalsefalsefalse2truefalsefalse00falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value.No authoritative reference available.falsefalseBeginning Balance4false0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNetus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalse2truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis element represents [net] transfers in to and out of liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(3) falsefalseNet transfers in to (out of) Level 35false0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchasesSalesIssuancesSettlementsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6480000064.8falsefalsefalsefalsefalse2truefalsefalse110000000110.0falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(2) falsefalsePurchases, sales, settlements, issuances, net6false0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarningsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse2270000022.7falsefalsefalsefalsefalse2truefalsefalse10000001.0falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis element represents total gains or losses for the period (realized and unrealized), arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(1) falsefalseTotal realized and unrealized gains (losses)7false0wpi_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValuewpifalsecreditinstantFair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value.falsefalsefalsefalsefalsefalsefalsefalsetruefalseperiodendlabel1truefalsefalse198500000198.5falsetruefalsefalsefalse2truefalsefalse111000000111.0falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value.No authoritative reference available.falsefalseEnding Balance26Fair Value Measurement (Details 1) (Contingent consideration obligation [member], USD $)HundredThousandsUnKnownUnKnownUnKnownfalsetrue