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Debt - Narrative (Details) |  |  |  |  |  |  | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2022 USD ($) | Jan. 14, 2022 USD ($) | Oct. 01, 2021 USD ($) | Apr. 01, 2021 USD ($) | Mar. 31, 2021 | Mar. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) creditFacility | Jun. 30, 2021 USD ($) | Sep. 30, 2021 USD ($)
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from issuance of long-term debt |  |  |  |  |  |  | $ 798,802,000 | $ 2,797,346,000 |
Long-term debt |  |  |  |  |  |  | $ 7,960,000,000 |  | $ 7,360,000,000
Maximum debt-to-total-capitalization ratio |  |  |  |  |  |  | 70.00% |  |
Debt-to-total-capitalization ratio |  |  |  |  |  |  | 0.47 |  |
Minimum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Equity-to-total-capitalization ratio |  |  |  |  |  |  | 50.00% |  |
Outstanding indebtedness |  |  |  |  |  |  | $ 15,000,000 |  |
Maximum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Equity-to-total-capitalization ratio |  |  |  |  |  |  | 60.00% |  |
Outstanding indebtedness |  |  |  |  |  |  | $ 100,000,000 |  |
Revolving Credit Facility |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | $ 2,500,000,000 |  |
Number of credit facilities | creditFacility |  |  |  |  |  |  | 4 |  |
Unsecured 1.50% Senior Notes, due 2031 |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  | $ 600,000,000 |  |  |  |  |  |
Interest rate |  |  | 2.85% |  |  |  | 1.50% |  |
Effective interest rate |  |  | 2.58% |  |  |  |  |  |
Proceeds from issuance of long-term debt |  |  | $ 589,800,000 |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  | $ 600,000,000 |  | 600,000,000
Unsecured 2.625% Senior Notes, due 2029 |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  | $ 200,000,000 |  |  |  |  |  |  |
Interest rate |  | 2.625% |  |  |  |  | 2.625% |  |
Effective interest rate |  | 2.54% |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  | $ 500,000,000 |  | 300,000,000
Floating-rate term loan, due April 2022 |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Repayments of debt |  | $ 200,800,000 |  |  |  |  |  |  |
Long-term debt |  | $ 200,000,000 |  |  |  |  | 0 |  | $ 200,000,000
Five Year Unsecured Revolving Credit Agreement |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Outstanding commercial paper |  |  |  |  |  |  | 0 |  |
Five Year Unsecured Revolving Credit Agreement | Commercial Paper |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | $ 1,500,000,000 | 1,500,000,000 |  |
Debt agreement term |  |  |  |  |  | 5 years |  |  |
Accordion feature | $ 250,000,000 |  |  |  |  |  |  |  |
Maximum borrowing capacity post accordion feature | 1,750,000,000 |  |  |  |  |  |  |  |
$900 Million Revolving Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | $ 900,000,000 |  |
Debt agreement term |  |  |  |  |  |  | 3 years |  |
Accordion feature | 100,000,000 |  |  |  |  |  |  |  |
Maximum borrowing capacity post accordion feature | 1,000,000,000 |  |  |  |  |  |  |  |
Outstanding borrowings |  |  |  |  |  |  | $ 0 |  |
$50 Million Bank Loan Agreement | Line of Credit |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  | $ 50,000,000 |  |  |  |  |
Debt agreement term |  |  |  | 364 days |  |  |  |  |
Outstanding borrowings |  |  |  |  |  |  | 0 |  |
$50 Million Revolving Credit Facility |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Outstanding borrowings |  |  |  |  |  |  | 0 |  |
$50 Million Revolving Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Maximum borrowing capacity | $ 50,000,000 |  |  |  |  |  |  |  |
Debt agreement term | 364 days |  |  |  |  |  |  |  |
Remaining borrowing capacity |  |  |  |  |  |  | $ 44,400,000 |  |
Base Rate | Five Year Unsecured Revolving Credit Agreement | Minimum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 0.00% |  |  |  |
Base Rate | Five Year Unsecured Revolving Credit Agreement | Maximum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 0.25% |  |  |  |
Base Rate | $900 Million Revolving Credit Facility | Revolving Credit Facility | Minimum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 0.00% |  |  |  |
Base Rate | $900 Million Revolving Credit Facility | Revolving Credit Facility | Maximum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 0.25% |  |  |  |
SOFR | Five Year Unsecured Revolving Credit Agreement | Minimum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 0.75% |  |  |  |
SOFR | Five Year Unsecured Revolving Credit Agreement | Maximum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 1.25% |  |  |  |
SOFR | $900 Million Revolving Credit Facility | Revolving Credit Facility | Minimum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 0.75% |  |  |  |
SOFR | $900 Million Revolving Credit Facility | Revolving Credit Facility | Maximum |  |  |  |  |  |  |  |  |
Line Of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |
Interest rate spread |  |  |  |  | 1.25% |  |  |  |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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