Commitments, Contingencies and Other Contractual Arrangements - Aircraft-Related Commitments and Financing Arrangements and Other Commitments (Details)	2 Months Ended	3 Months Ended	7 Months Ended
	Mar. 12, 2025 USD ($)	Sep. 30, 2025 USD ($) aircraft aircraftEngine	Sep. 30, 2025 USD ($) aircraft aircraftEngine	Oct. 10, 2025 aircraft lease	Mar. 13, 2025 aircraftEngine
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of delivered aircraft with secured debt financing commitments | aircraft		48	48
Aircraft-Related Secured Debt
Unrecorded Unconditional Purchase Obligation [Line Items]
Interest commitments, remainder of fiscal year		$ 16,900,000	$ 16,900,000
Interest commitments, 2026		45,900,000	45,900,000
Interest commitments, 2027		36,900,000	36,900,000
Interest commitments, 2028		18,700,000	18,700,000
Interest commitments, 2029		9,600,000	9,600,000
Interest commitments, 2030 and thereafter		3,500,000	3,500,000
PW1100 GTF Engine
Unrecorded Unconditional Purchase Obligation [Line Items]
Vendor consideration credit, expense offset, total amount received		117,100,000	117,100,000
Vendor consideration credit, expense offset, asset basis reduction		14,100,000
Vendor consideration credit, depreciation and amortization, asset basis reduction	$ 6,100,000	9,200,000	16,400,000
PW1100 GTF Engine | Aircraft Maintenance, Materials, and Repairs
Unrecorded Unconditional Purchase Obligation [Line Items]
Vendor consideration credit, expense offset		4,400,000
Aircraft and Related Flight Equipment
Unrecorded Unconditional Purchase Obligation [Line Items]
Committed expenditures, remainder of fiscal year		2,800,000	2,800,000
Committed expenditures, 2026		22,100,000	22,100,000
Committed expenditures, 2027		183,000,000.0	183,000,000.0
Committed expenditures, 2028		297,800,000	297,800,000
Committed expenditures, 2029		1,124,300,000	1,124,300,000
Committed expenditures, 2030 and thereafter		1,857,800,000	1,857,800,000
Non-aircraft Related Commitments
Unrecorded Unconditional Purchase Obligation [Line Items]
Committed expenditures, remainder of fiscal year		13,200,000	13,200,000
Committed expenditures, 2026		42,000,000.0	42,000,000.0
Committed expenditures, 2027		34,600,000	34,600,000
Committed expenditures, 2028		7,600,000	7,600,000
Committed expenditures, 2029		2,000,000.0	2,000,000.0
Committed expenditures, 2030 and thereafter		3,700,000	3,700,000
Airbus
Unrecorded Unconditional Purchase Obligation [Line Items]
Future aircraft to be received | aircraftEngine					27
Third Party Lessor | A320 and A321
Unrecorded Unconditional Purchase Obligation [Line Items]
Aircraft rent commitments, remainder of fiscal year		0	0
Aircraft rent commitments, 2026		0	0
Aircraft rent commitments, 2027		62,300,000	62,300,000
Aircraft rent commitments, 2028		159,300,000	159,300,000
Aircraft rent commitments, 2029		206,500,000	206,500,000
Aircraft rent commitments, 2030 and beyond		$ 2,050,000,000	$ 2,050,000,000
AerCap | Subsequent Event
Unrecorded Unconditional Purchase Obligation [Line Items]
Bankruptcy proceedings, transfer of purchase rights and options, terms adjustment, number of aircraft | aircraft				52
Bankruptcy proceedings, number of leases assumed | lease				10
Bankruptcy proceedings, number of leases rejected | lease				27
Bankruptcy proceedings, number of new leases entered | lease				30
2029 Through 2031 | Airbus
Unrecorded Unconditional Purchase Obligation [Line Items]
Future aircraft to be received | aircraft		52	52
2024 Through 2031 | PurePower PW1100G-JM Engine
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of spare aircraft engines ordered | aircraftEngine		16	16
2024 Through 2031 | Airbus
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of aircraft without secured financing commitments scheduled for delivery | aircraft		52	52
2027 Through 2028 | Third Party Lessor | A320 and A321
Unrecorded Unconditional Purchase Obligation [Line Items]
Future aircraft to be received | aircraft		36	36