Details of Selected Consolidated Balance Sheet Captions - Goodwill Detail Table (Details) $ in Thousands	12 Months Ended
Sep. 30, 2020 USD ($)
Goodwill [Roll Forward]
Goodwill beginning balance	$ 730,706
Deferred tax adjustments on prior acquisitions	551
Goodwill ending balance	731,257
Goodwill, Period Increase (Decrease)	600
Distribution
Goodwill [Roll Forward]
Goodwill beginning balance	587,604
Deferred tax adjustments on prior acquisitions	(768)
Goodwill ending balance	586,836
Pipeline and Storage
Goodwill [Roll Forward]
Goodwill beginning balance	143,102
Deferred tax adjustments on prior acquisitions	1,319
Goodwill ending balance	$ 144,421

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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