Shareholders' Equity - Narrative (Details) - USD ($)	9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Class of Stock [Line Items]
Forward sales equity agreement, settlement in cash	$ 550,735,000
Net proceeds from equity issuances	749,987,000	$ 671,630,000
Shelf Registration Statement
Class of Stock [Line Items]
Debt and equity securities authorized for issuance	5,000,000,000.0
Debt and equity securities authorized for issuance value remaining	1,800,000,000
At-The-Market
Class of Stock [Line Items]
Value of shares authorized for issuance	$ 1,000,000,000
Forward sales equity agreement (in shares)	7,224,450
Forward sales equity agreement, settlement in cash	$ 833,200,000
Shares issued (in shares)	6,401,469
Net proceeds from equity issuances	$ 750,000,000.0
Equity available for issuance	$ 845,700,000