Shareholders' Equity - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Class of Stock [Line Items]
Forward sales equity agreement, settlement in cash	$ 1,684,406
Net proceeds from equity issuances	568,603	$ 749,987
Shelf Registration Statement
Class of Stock [Line Items]
Debt and equity securities authorized for issuance	8,000,000
Debt and equity securities authorized for issuance value remaining	5,800,000
At-The-Market
Class of Stock [Line Items]
Value of shares authorized for issuance	$ 1,700,000
Forward sales equity agreement (in shares)	5,967,768
Forward sales equity agreement, settlement in cash	$ 871,500
Shares issued (in shares)	4,907,436
Net proceeds from equity issuances	$ 568,600
Equity available for issuance	$ 828,500