v3.26.1
Pension and Other Postretirement Benefits (Fair Value of Pension Plan Assets and Asset Allocations) (Details) - USD ($)
$ in Millions
Apr. 30, 2026
Apr. 30, 2025
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets $ 514 $ 576
Level 1 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 22 25
Level 2 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 260 242
Level 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 0 1
Fair Value, Inputs, Level 1, 2 and 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 282 268
Equity Securities [Member] | Level 1 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 22 25
Equity Securities [Member] | Level 2 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 0 0
Equity Securities [Member] | Level 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 0 0
Equity Securities [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 22 25
Fixed Income Investments [Member] | Level 1 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 0 0
Fixed Income Investments [Member] | Level 2 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 260 242
Fixed Income Investments [Member] | Level 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 0 0
Fixed Income Investments [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets 260 242
Limited Partnership Interests [Member] | Level 1 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [1]   0
Limited Partnership Interests [Member] | Level 2 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [1]   0
Limited Partnership Interests [Member] | Level 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [1]   1
Limited Partnership Interests [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [1]   1
Limited Partnership Interests [Member] | Fair Value Measured at Net Asset Value Per Share [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [2],[3] 40 47
Equity Funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [2],[4] 110 115
Fixed Income Funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [2],[4] 26 28
Real Estate funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [2],[4] 39 41
Short-term Investments [Member] | Fair Value Measured at Net Asset Value Per Share [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets [2],[4] 15 75
Net receivable (payable) for pending transactions [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Total, Plan Assets $ 2 $ 2
[1] This limited partnership interest was initially valued at cost and has been adjusted to fair value as determined in good faith by management of the partnership using various factors, and does not meet the requirements for reporting at the net asset value (NAV). The valuation requires significant judgment due to the absence of quoted market prices and the inherent lack of liquidity.
[2] Certain investments that were measured using NAV (or its equivalent) as a practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to total plan assets.
[3] These limited partnership interests were initially valued at cost and have been adjusted using NAV per audited financial statements. Investments are generally not eligible for immediate redemption and have original terms averaging 10 to 13 years, although those periods may be extended.
[4] Commingled trust fund valuations are based on the NAV of the funds as determined by the fund administrators and reviewed by us. NAV represents the underlying assets owned by the fund, minus liabilities and divided by the number of shares or units outstanding. Generally, for commingled trust funds other than real estate, redemptions are permitted daily with no notice period. The real estate fund is redeemable quarterly with 110 days’ notice.