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Operating Revenue (Details)	3 Months Ended
	Mar. 31, 2021 segment division
Revenue from Contract with Customer [Abstract]
Number of company divisions | division	83
Number of reportable segments | segment	7

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- Definition

Number of Company Divisions

+ References

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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No definition available.

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