Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt - Schedule of Debt Instruments (Details)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 GBP (£)	May 31, 2020 USD ($)	Sep. 30, 2019 USD ($)
Debt Instrument [Line Items]
Long-term debt	$ 4,140,351,000			$ 4,172,892,000
Less AmerisourceBergen Corporation current portion	399,928,000			32,573,000
Total, net of current portion	3,620,641,000			4,033,880,000
Revolving credit note
Debt Instrument [Line Items]
Maximum borrowing capacity	75,000,000
Long-term debt	0			0
Term loan due in 2020
Debt Instrument [Line Items]
Long-term debt	399,928,000			399,778,000
Overdraft facility due 2021 (£30,000)
Debt Instrument [Line Items]
Maximum borrowing capacity \| £		£ 30,000,000
Long-term debt	0			32,573,000
Receivables securitization facility due 2022
Debt Instrument [Line Items]
Maximum borrowing capacity	1,450,000,000
Long-term debt	350,000,000			350,000,000
Multi-currency revolving credit facility due 2024
Debt Instrument [Line Items]
Maximum borrowing capacity	1,400,000,000
Long-term debt	0			0
$500,000, 3.50% senior notes due 2021
Debt Instrument [Line Items]
Long-term debt	0			498,908,000
$500,000, 3.50% senior notes due 2021 \| Senior notes
Debt Instrument [Line Items]
Principal amount	$ 500,000,000		$ 500,000,000
Interest rate	3.50%	3.50%	3.50%
$500,000, 3.40% senior notes due 2024
Debt Instrument [Line Items]
Long-term debt	$ 498,110,000			497,744,000
$500,000, 3.40% senior notes due 2024 \| Senior notes
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	3.40%	3.40%
$500,000, 3.25% senior notes due 2025
Debt Instrument [Line Items]
Long-term debt	$ 496,819,000			496,311,000
$500,000, 3.25% senior notes due 2025 \| Senior notes
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	3.25%	3.25%
$750,000, 3.45% senior notes due 2027
Debt Instrument [Line Items]
Long-term debt	$ 743,730,000			743,099,000
$750,000, 3.45% senior notes due 2027 \| Senior notes
Debt Instrument [Line Items]
Principal amount	$ 750,000,000
Interest rate	3.45%	3.45%
$500,000, 2.80% senior notes due 2030
Debt Instrument [Line Items]
Long-term debt	$ 493,983,000			0
$500,000, 2.80% senior notes due 2030 \| Senior notes
Debt Instrument [Line Items]
Principal amount	$ 500,000,000		$ 500,000,000
Interest rate	2.80%	2.80%	2.80%
$500,000, 4.25% senior notes due 2045
Debt Instrument [Line Items]
Long-term debt	$ 494,676,000			494,514,000
$500,000, 4.25% senior notes due 2045 \| Senior notes
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	4.25%	4.25%
$500,000, 4.30% senior notes due 2047
Debt Instrument [Line Items]
Long-term debt	$ 492,688,000			492,488,000
$500,000, 4.30% senior notes due 2047 \| Senior notes
Debt Instrument [Line Items]
Principal amount	$ 500,000,000
Interest rate	4.30%	4.30%
Nonrecourse debt
Debt Instrument [Line Items]
Long-term debt	$ 170,417,000			167,477,000
Less AmerisourceBergen Corporation current portion	$ 119,782,000			$ 106,439,000