Fair Value Measurements - Fair Value, Assets Measured on Nonrecurring Basis, Valuation Techniques (Details) - USD ($) $ in Millions	Jun. 30, 2024	Jun. 30, 2023
Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 15
Fair Value, Nonrecurring | Operating lease equipment
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	15
Valuation, Market Approach | Aircraft value publications
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Range Median or Average	23
Valuation, Market Approach | Aircraft condition adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Range Median or Average	(8)
Valuation, Market Approach | Minimum | Aircraft value publications
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Range Median or Average	21
Valuation, Market Approach | Minimum | Aircraft condition adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Range Median or Average	(8)
Valuation, Market Approach | Maximum | Aircraft value publications
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Range Median or Average	27
Valuation, Market Approach | Maximum | Aircraft condition adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Range Median or Average	0
Valuation, Market Approach | Level 3 | Fair Value, Nonrecurring | Operating lease equipment
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 15