| DeprecatedDate | 2020-01-31 | http://fasb.org/srt/role/changeNote/changeNote |
| DeprecatedLabel | Element was deprecated due to remodeling of topic area. | http://fasb.org/srt/role/changeNote/changeNote |
| DeprecationReplacement | MultiemployerPlanPensionSignificantCertifiedZoneStatusExtendedAmortizationProvision MultiemployerPlanPensionInsignificantCertifiedZoneStatusExtendedAmortizationProvision | http://fasb.org/srt/role/changeNote/changeNote |
| TaxonomyVersion | 2018 | http://fasb.org/srt/role/changeNote/changeNote |
| ChangeDate | 2017-07 | http://fasb.org/srt/role/changeNote/changeNote |
| ModifiedLabels | true | http://fasb.org/srt/role/changeNote/changeNote |
| ModifiedDocumentation | true | http://fasb.org/srt/role/changeNote/changeNote |
| PreviousDocumentation | Indicate (true/false) whether the multiemployer plan has utilized any extended amortization provisions that affect the calculation of the zone status. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. | http://fasb.org/srt/role/changeNote/changeNote |
| SourceName | Retirement Benefits:Taxonomy Technical Improvement | http://fasb.org/srt/role/changeNote/changeNote |
| TaxonomyVersion | 2020 | http://fasb.org/srt/role/changeNote/changeNote |
| ChangeDate | 2019-10 | http://fasb.org/srt/role/changeNote/changeNote |
| ElementDeprecated | true | http://fasb.org/srt/role/changeNote/changeNote |