Capitalization and Short-Term Borrowings (Tables)

12 Months Ended

Sep. 30, 2025

Capitalization, Long-Term Debt and Equity [Abstract]

Schedule of Changes in Common Stock Equity

Summary of Changes in Common Stock Equity

	Common Stock			Paid In Capital		Earnings Reinvested in the Business		Accumulated Other Comprehensive Income (Loss)
	Shares	Amount
	(Thousands, except per share amounts)
Balance at September 30, 2022	91,478	$	91,478	$	1,027,066	$	1,587,085	$	(625,733)
Net Income Available for Common Stock						476,866
Dividends Declared on Common Stock ($1.94 Per Share)						(178,095)
Other Comprehensive Income, Net of Tax								570,673
Share-Based Payment Expense(1)				18,746
Common Stock Issued (Repurchased) Under Stock and Benefit Plans	341	341		(5,051)
Balance at September 30, 2023	91,819	91,819		1,040,761		1,885,856		(55,060)
Net Income Available for Common Stock						77,513
Dividends Declared on Common Stock ($2.02 Per Share)						(185,220)
Other Comprehensive Income, Net of Tax								39,584
Share-Based Payment Expense(1)				19,868
Common Stock Issued (Repurchased) Under Stock and Benefit Plans	333	333		(1,955)
Share Repurchases Under Repurchase Plan	(1,146)	(1,146)		(13,187)		(50,823)
Balance at September 30, 2024	91,006	91,006		1,045,487		1,727,326		(15,476)
Net Income Available for Common Stock						518,504
Dividends Declared on Common Stock ($2.10 Per Share)						(189,919)
Other Comprehensive Loss, Net of Tax								(43,746)
Share-Based Payment Expense(1)				17,306
Common Stock Issued (Repurchased) Under Stock and Benefit Plans	202	202		(2,262)
Share Repurchases Under Repurchase Plan	(829)	(829)		(9,613)		(43,382)
Balance at September 30, 2025	90,379	$	90,379	$	1,050,918	$	2,012,529	$	(59,222)

(1)Paid in Capital includes compensation costs associated with performance shares and/or restricted stock awards. The expense is included within Net Income Available for Common Stock, net of tax benefits.

Schedule of Share-Based Compensation for Non-Performance Based Restricted Stock Units

Transactions for 2025 involving nonperformance-based restricted stock units for all plans are summarized as follows:

	Number of Restricted Stock Units	Weighted Average Fair Value per Award
Outstanding at September 30, 2024	438,193	$	46.70
Granted in 2025	132,352	$	58.64
Vested in 2025	(128,028)	$	49.14
Forfeited in 2025	(13,270)	$	50.78
Outstanding at September 30, 2025	429,247	$	49.53

Schedule of Share-Based Compensation for Performance Shares

Transactions for 2025 involving performance shares for all plans are summarized as follows:

	Number of Performance Shares	Weighted Average Fair Value per Award
Outstanding at September 30, 2024	719,577	$	54.69
Granted in 2025	239,042	$	55.43
Vested in 2025	(108,799)	$	56.98
Forfeited in 2025	(206,823)	$	61.05
Change in Units Based on Performance Achieved	9,478	$	53.47
Outstanding at September 30, 2025	652,475	$	52.55

Schedule of Weighted Average Assumptions Used in Estimating Fair Value

The following weighted average assumptions were used in estimating the fair value of the TSR Performance Shares at the date of grant:

	Year Ended September 30
	2025		2024		2023
Risk-Free Interest Rate	4.11	%	4.36	%	4.03	%
Remaining Term at Date of Grant (Years)	2.82		2.98		2.80
Expected Volatility	23.2	%	23.9	%	31.6	%
Expected Dividend Yield (Quarterly)	N/A		N/A		N/A

Schedule of Long-Term Debt

The outstanding long-term debt is as follows:

	At September 30
	2025		2024
	(Thousands)
Medium-Term Notes(1):
7.38% due June 2025	$	—	$	50,000
Notes(1)(2)(3):
2.95% to 5.95% due October 2026 to March 2035	2,400,000		2,350,000
Delayed Draw Term Loan(4):
Variable Rate due February 2026	300,000		300,000
Total Long-Term Debt	2,700,000		2,700,000
Less Unamortized Discount and Debt Issuance Costs	17,139		11,757
Less Current Portion(5)	300,000		500,000
	$	2,382,861	$	2,188,243

(1)The Medium-Term Notes and Notes are unsecured.

(2)The holders of these notes may require the Company to repurchase their notes at a price equal to 101% of the principal amount in the event of both a change in control and a ratings downgrade to a rating below investment grade.

(3)The interest rate payable on $300.0 million of 4.75% notes, $300.0 million of 3.95% notes, $500.0 million of 2.95% notes and $300.0 million of 5.50% notes will be subject to adjustment from time to time, with a maximum of 2.00%, if certain change of control events involving a material subsidiary result in a downgrade of the credit rating assigned to the notes to below investment grade (or if the credit rating assigned to the notes is subsequently upgraded). The interest rate payable on $500.0 million of 5.50% notes and $500.0 million of 5.95% notes will be subject to adjustment from time to time, with a maximum adjustment of 2.00%, such that the coupon will not exceed 7.50% on the 5.50% notes and 7.95% on the 5.95% notes, if certain change in control events involving a material subsidiary result in a downgrade of the credit rating assigned to the notes to a rating below investment grade. A downgrade with a resulting increase to the coupon does not preclude the coupon from returning to its original rate if the Company’s credit rating is subsequently upgraded.

(4)The interest rate on the delayed draw term loan, which is based on a weighted average SOFR interest rate, was 5.62% and 6.71% as of September 30, 2025 and September 30, 2024, respectively. The current weighted average locked-in interest rate is 5.43% until mid-December 2025.

(5)Current Portion of Long-Term Debt at September 30, 2025 consisted of a $300.0 million long-term delayed draw term loan that matures in February 2026. Current Portion of Long-Term Debt at September 30, 2024 consisted of $50.0 million of 7.38% medium-term notes and $450.0 million of 5.20% notes.