Short-Term Financing - Commercial Paper and Reverse Repurchase Agreements (Details) - USD ($) $ in Billions	12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Commercial Paper
Short-term Debt [Line Items]
Short-term debt, average outstanding amount	$ 4.1	$ 3.5
Weighted average interest rates	4.80%	5.30%
Weighted average maturity (approximately in days)	2 days	2 days
Reverse Repurchase Agreements
Short-term Debt [Line Items]
Short-term debt, average outstanding amount	$ 2.9	$ 1.8
Weighted average interest rates	4.80%	5.50%