Property, Plant and Equipment (Tables)

12 Months Ended

Sep. 30, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

At September 30, 2020, estimated useful lives by asset type were as follows:

Asset Type	Minimum Estimated Useful Life (in years)	Maximum Estimated Useful Life (in years)
Buildings and improvements	10	40
Equipment, primarily cylinders and tanks	5	30
Electricity generation facilities	25	40
Pipeline and related assets	25	40
Transportation equipment and office furniture and fixtures	3	10
Computer software	1	10

Property, plant and equipment comprise the following at September 30:

	2020		2019
Utility:
Distribution	$	3,630	$	3,366
Transmission	111		106
General and other	425		389
Work in process	99		77
Total Utility	4,265		3,938
Non-utility:
Land	191		184
Buildings and improvements	431		404
Transportation equipment	248		258
Equipment, primarily cylinders and tanks	3,712		3,455
Electric generation	211		327
Pipeline and related assets	1,098		1,150
Other	306		255
Work in process	196		102
Total non-utility	6,393		6,135
Total property, plant and equipment	$	10,658	$	10,073