XML 105 R89.htm IDEA: XBRL DOCUMENT
v3.21.2

Pension Plans - Percentage of Total Plan Assets (Details) - Pension Plan | Sep. 30, 2021 | Sep. 30, 2020
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Asset Category | 100.00% | 100.00%
Equity Securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Asset Category | 35.00% | 33.00%
Fixed Income Securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Asset Category | 34.00% | 34.00%
Commodity Option |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Asset Category | 11.00% | 11.00%
Insurance Company |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Asset Category | 12.00% | 13.00%
Options |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Asset Category | 1.00% | 1.00%
Cash |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Asset Category | 7.00% | 8.00%

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_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_FixedIncomeSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_CommodityOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ptc_InsuranceCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ptc_OptionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_CashMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |