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Shareholders' Equity - Narrative (Details) - USD ($) | 9 Months Ended |
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Mar. 23, 2022
Class of Stock [Line Items] |  |  |
Net proceeds available | $ 700,895,000 |  |
Net proceeds from equity issuances | 675,320,000 | $ 460,678,000 |
Shelf Registration Statement |  |  |
Class of Stock [Line Items] |  |  |
Debt and equity securities authorized for issuance | 5,000,000,000 |  |
Debt and equity securities authorized for issuance value remaining | 2,200,000,000 |  |
At-The-Market |  |  |
Class of Stock [Line Items] |  |  |
Equity available for issuance | $ 663,000,000 |  | $ 1,000,000,000
Forward sales equity agreement (in shares) | 10,308,214 |  |
Net proceeds available | $ 1,100,000,000 |  |
Stock issued during period, new issues (in shares) | 6,932,722 |  |
Net proceeds from equity issuances | $ 675,300,000 |  |

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