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Segment and Non-Tariffed Business Reporting - Narrative (Details)	9 Months Ended
	Sep. 30, 2023 subsidiary
Segment Reporting [Abstract]
Number of subsidiaries	4

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- Definition

Number Of Subsidiaries

+ References

No definition available.

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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