| 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 |
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| SourceName | Reference Project:Taxonomy Technical Improvement | http://fasb.org/srt/role/changeNote/changeNote |
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| ChangeDate | 2019-11 | http://fasb.org/srt/role/changeNote/changeNote |
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| ChangeDate | 2017-08 | http://fasb.org/srt/role/changeNote/changeNote |
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