v3.25.2
Fair Value Measurements (Tables)
 6 Months Ended
Jun. 30, 2025
Fair Value Disclosures [Abstract]  
Schedule of Carrying Amount and Estimated Fair Value, Long-term Debt The carrying amounts and estimated fair values of the Company's long-term debt at June 30, 2025 and December 31, 2024 were as follows (in millions):
SuccessorPredecessor
June 30, 2025December 31, 2024Fair Value Level Hierarchy
 Carrying ValueEstimated Fair ValueCarrying ValueEstimated Fair Value
DIP term loans$— $— $309.0 $309.0 Level 3
Fixed-rate term loans880.2 848.1 972.2 970.7 Level 3
Unsecured term loans136.3 135.2 136.3 130.4 Level 3
2015-1 EETC Class A 223.6 203.7 234.6 215.8 Level 2
2017-1 EETC Class AA154.3 131.8 160.3 140.4 Level 2
2017-1 EETC Class A51.4 42.7 53.4 45.8 Level 2
2017-1 EETC Class B— — 44.7 40.5 Level 2
2025-1 EETC Class B215.0 196.8 — — Level 2
Revolving credit facility— — 300.0 300.0 Level 3
Exit secured notes850.3 614.5 — — Level 2
Total long-term debt$2,511.1 $2,172.8 $2,210.5 $2,152.6 
8.00% senior secured notes
$— $— $1,110.0 $1,117.9 Level 3
4.75% convertible notes due 2025
— — 25.1 8.8 Level 2
1.00% convertible notes due 2026
— — 500.0 166.4 Level 2
Total liabilities subject to compromise$— $— $1,635.1 $1,293.1 
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis Assets and liabilities measured at gross fair value on a recurring basis are summarized below (in millions):
 Successor Fair Value Measurements as of June 30, 2025
 TotalLevel
1		Level
2		Level
3
Cash and cash equivalents$407.5 $407.5 $— $— 
Restricted cash152.1 152.1 — — 
Short-term investment securities— — — — 
Assets held for sale449.1 — — 449.1 
Total assets$1,008.7 $559.6 $— $449.1 
Total liabilities$— $— $— $— 
 Predecessor Fair Value Measurements as of December 31, 2024
 TotalLevel
1		Level
2		Level
3
Cash and cash equivalents$902.1 $902.1 $— $— 
Restricted cash168.4 168.4 — — 
Short-term investment securities118.3 118.3 — — 
Assets held for sale463.0 — — 463.0 
Total assets$1,651.8 $1,188.8 $— $463.0 
Total liabilities$— $— $— $—