| PublishDate | 2018-01 | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| Source | Taxonomy Implementation Guide | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| SourceName | Retirement Benefits-Phase 2 | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| pdfURI | https://www.fasb.org/retirementbenefitsphase2_2020 | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| Note | Element is modeled from balance sheet perspective. | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| PublishDate | 2017-01 | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| Positive_XBRL_Value | Enter a positive XBRL value for increase in plan assets from actual return. | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| Negative_XBRL_Value | Enter a negative XBRL value for decrease in plan assets from actual loss. | http://fasb.org/us-gaap/role/tin/taxonomyImplementationNote |
| SourceName | Retirement Benefits:Taxonomy Technical Improvement | http://fasb.org/srt/role/changeNote/changeNote |
| TaxonomyVersion | 2018 | http://fasb.org/srt/role/changeNote/changeNote |
| ChangeDate | 2017-08 | http://fasb.org/srt/role/changeNote/changeNote |
| ModifiedReferences | true | http://fasb.org/srt/role/changeNote/changeNote |
| Publisher | FASB | http://www.xbrl.org/2003/role/disclosureRef |
| Name | Accounting Standards Codification | http://www.xbrl.org/2003/role/disclosureRef |
| Topic | 715 | http://www.xbrl.org/2003/role/disclosureRef |
| SubTopic | 20 | http://www.xbrl.org/2003/role/disclosureRef |
| Section | 50 | http://www.xbrl.org/2003/role/disclosureRef |
| Paragraph | 1 | http://www.xbrl.org/2003/role/disclosureRef |
| Subparagraph | (d)(iv)(02)(A) | http://www.xbrl.org/2003/role/disclosureRef |
| URI | http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 | http://www.xbrl.org/2003/role/disclosureRef |
| Publisher | FASB | http://www.xbrl.org/2003/role/exampleRef |
| Name | Accounting Standards Codification | http://www.xbrl.org/2003/role/exampleRef |
| Topic | 715 | http://www.xbrl.org/2003/role/exampleRef |
| SubTopic | 20 | http://www.xbrl.org/2003/role/exampleRef |
| Section | 55 | http://www.xbrl.org/2003/role/exampleRef |
| Paragraph | 17 | http://www.xbrl.org/2003/role/exampleRef |
| URI | http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 | http://www.xbrl.org/2003/role/exampleRef |