XML 80 R62.htm IDEA: XBRL DOCUMENT
v3.20.4

Employee Benefit Plans, Weighted-Average Assumptions Used (Details) - Defined Benefit Pension Plans Combined [Member] - Stock | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Weighted-Average Assumptions Used to Determine Benefit Obligations [Abstract] |  |
Discount rate | 2.30% | 3.10%
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost [Abstract] |  |
Discount rate | 3.10% | 4.10%
Expected long-term return on plan assets | 6.50% | 6.50%
Target Asset Allocations [Abstract] |  |
Percentage by which the return on plan assets should exceed the annual rate of inflation | 3.00% |
Maximum equity securities holdings in any one company | 5.00% |
Minimum number of individual stocks that must be included in the domestic stock portfolio | 20 |
Minimum number of individual stocks that must be included in the international stock portfolio | 30 |
Maximum fixed income securities holdings in any single issuer | 5.00% |
Minimum [Member] |  |
Weighted-Average Assumptions Used to Determine Benefit Obligations [Abstract] |  |
Rate of compensation increase | 2.50% | 2.50%
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost [Abstract] |  |
Rate of compensation increase | 2.50% | 2.50%
Target Asset Allocations [Abstract] |  |
Investment performance objectives benchmark period | 3 years |
Maximum equity securities holdings in any one industry | 20.00% |
Maximum [Member] |  |
Weighted-Average Assumptions Used to Determine Benefit Obligations [Abstract] |  |
Rate of compensation increase | 3.00% | 3.00%
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost [Abstract] |  |
Rate of compensation increase | 3.00% | 3.00%
Target Asset Allocations [Abstract] |  |
Investment performance objectives benchmark period | 5 years |
Maximum equity securities holdings in any one industry | 25.00% |
Equity Securities [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Asset allocation of plan assets | 50.00% |
Weighted-average target asset allocations | 50.00% |
Equity Securities [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Asset allocation of plan assets | 70.00% |
Weighted-average target asset allocations | 70.00% |
Large Cap [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 60.00% |
Large Cap [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 95.00% |
Mid Cap [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
Mid Cap [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 25.00% |
Small Cap [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
Small Cap [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 10.00% |
International Developed Nations [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
International Developed Nations [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 25.00% |
International Emerging Nations [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
International Emerging Nations [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 10.00% |
Fixed Income Securities [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Asset allocation of plan assets | 30.00% |
Weighted-average target asset allocations | 30.00% |
Fixed Income Securities [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Asset allocation of plan assets | 50.00% |
Weighted-average target asset allocations | 50.00% |
U.S. Treasuries [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 15.00% |
U.S. Treasuries [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 55.00% |
Federal Agency Securities [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
Federal Agency Securities [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 22.00% |
Corporate Bonds [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
Corporate Bonds [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 40.00% |
Mortgage-Backed Securities [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 15.00% |
Mortgage-Backed Securities [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 55.00% |
International [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
International [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 20.00% |
High Yield Bonds [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
High Yield Bonds [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 20.00% |
Cash and Cash Equivalents [Member] | Minimum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 0.00% |
Cash and Cash Equivalents [Member] | Maximum [Member] |  |
Target Asset Allocations [Abstract] |  |
Weighted-average target asset allocations | 10.00% |

X
- References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanAssetsTargetAllocationsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2919-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of target 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/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Refers the benchmark period for investment performance objective. + References No definition available. + Details
Name: | yorw_InvestmentPerformanceObjectivesBenchmarkPeriod
Namespace Prefix: | yorw_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Element represents the maximum equity securities holdings in any one company in percentage according to the established guidelines. + References No definition available. + Details
Name: | yorw_MaximumEquitySecuritiesHoldingsInAnyOneCompany
Namespace Prefix: | yorw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Element represents the maximum equity securities holdings in any one industry in percentage according to the established guidelines. + References No definition available. + Details
Name: | yorw_MaximumEquitySecuritiesHoldingsInAnyOneIndustry
Namespace Prefix: | yorw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Element represents the maximum fixed income securities holdings in any single issuer according to the established guidelines. + References No definition available. + Details
Name: | yorw_MaximumFixedIncomeSecuritiesHoldingsInAnySingleIssuer
Namespace Prefix: | yorw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The minimum number of individual stocks that must be included in the domestic stock portfolio according to the established guidelines. + References No definition available. + Details
Name: | yorw_MinimumNumberOfIndividualStocksThatMustBeIncludedInDomesticStockPortfolio
Namespace Prefix: | yorw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The minimum number of individual stocks that must be included in the international stock portfolio according to the established guidelines. + References No definition available. + Details
Name: | yorw_MinimumNumberOfIndividualStocksThatMustBeIncludedInInternationalStockPortfolio
Namespace Prefix: | yorw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Element represents the percentage by which the return on plan assets should exceed the annual rate of inflation. + References No definition available. + Details
Name: | yorw_PercentageByWhichReturnOnPlanAssetsShouldExceedAnnualRateOfInflation
Namespace Prefix: | yorw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
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_DefinedBenefitPlanEquitySecuritiesLargeCapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

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

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

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

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

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

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

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

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