Employee Severance, Litigation, and Other (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Restructuring Cost and Reserve [Line Items]
Employee severance		$ 34,401	$ 34,147	$ 36,694
Litigation and opioid-related costs		6,722,346	185,145	61,527
Acquisition-related deal and integration costs		15,958	43,184	33,912
Business transformation efforts		37,961	55,437	32,963
Other restructuring initiatives		(3,359)	12,561	18,424
Total employee severance, litigation, and other		6,807,307	330,474	183,520
Gain on the sale of a facility		19,100
Opioid Lawsuits and Investigations
Restructuring Cost and Reserve [Line Items]
Litigation and opioid-related costs	$ 6,600,000
Litigation settlement, accrued reserve, net of income tax benefit		$ 5,500,000
Litigation settlement, accrued reserve			$ 116,700
Legal fees				$ 68,500

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