XML 16 R54.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Commitments and Contingencies (Narrative) (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 30, 2013 | Sep. 30, 2013 | Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2013
Guarantee Obligations [Line Items] |  |  |  |  |
Lease expense for operating leases |  |  | $ 4,000,000 | $ 3,900,000 | $ 4,700,000
Additional bonding capacity |  |  | 431,200,000 |  |
Proceeds from legal settlements | $ 1,700,000 |  |  |  |
Liquidated damages |  |  | 5,400,000 |  |
Probable liquidated damages |  |  | 1,800,000 |  |
Loss contingency, estimate of actual or projected loss |  |  | 1,700,000 |  |
Facility Agreement | Powell (UK) Limited |  |  |  |  |
Guarantee Obligations [Line Items] |  |  |  |  |
Guarantee liability |  |  | 4,000,000 |  |
Revolving credit facility |  |  | 15,200,000 |  |
Amount of credit facility remaining borrowing capacity |  |  | 11,200,000 |  |
Financial Standby Letter of Credit |  |  |  |  |
Guarantee Obligations [Line Items] |  |  |  |  |
Guarantee liability |  |  | 21,100,000 |  |
Performance Guarantee |  |  |  |  |
Guarantee Obligations [Line Items] |  |  |  |  |
Guarantee liability |  |  | 318,800,000 |  |
Acheson Alberta Canada |  |  |  |  |
Guarantee Obligations [Line Items] |  |  |  |  |
Loss on sublease and write-off of leasehold improvements |  |  | $ 800,000 |  |
Edmonton Alberta Canada |  |  |  |  |
Guarantee Obligations [Line Items] |  |  |  |  |
Loss on sublease and write-off of leasehold improvements |  | $ 1,700,000 |  |  |

X
- Definition Commitments and contingencies additional bonding capacity. + References No definition available. + Details
Name: | powl_CommitmentsAndContingenciesAdditionalBondingCapacity
Namespace Prefix: | powl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Loss contingency probable loss in period. + References No definition available. + Details
Name: | powl_LossContingencyProbableLossInPeriod
Namespace Prefix: | powl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Operating leases rent expense loss on sublease and write-off of leasehold improvements. + References No definition available. + Details
Name: | powl_OperatingLeasesRentExpenseLossOnSubleaseAndWriteOffOfLeaseholdImprovements
Namespace Prefix: | powl_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 + Details
Name: | us-gaap_GuaranteeObligationsCurrentCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_GuaranteeObligationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 + Details
Name: | us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 + Details
Name: | us-gaap_LossContingencyLossInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717 + Details
Name: | us-gaap_OperatingLeasesRentExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Cash received for the settlement of litigation during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585 + Details
Name: | us-gaap_ProceedsFromLegalSettlements
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentAxis=powl_FacilityAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=powl_PowellUKLimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_FinancialStandbyLetterOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_PerformanceGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=powl_AchesonAlbertaCanadaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=powl_EdmontonAlbertaCanadaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |