LEASES - Operating Lease Terms (Details) - aircraft  | 
Mar. 31, 2021  | 
Mar. 31, 2020  | 
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| Operating Leased Assets [Line Items] | ||
| Number of Aircraft | 44 | 46 | 
| Fiscal year 2022 to fiscal year 2023 | ||
| Operating Leased Assets [Line Items] | ||
| Number of Aircraft | 15 | |
| Fiscal year 2024 to fiscal year 2025 | ||
| Operating Leased Assets [Line Items] | ||
| Number of Aircraft | 19 | |
| Fiscal year 2026 to fiscal year 2027 | ||
| Operating Leased Assets [Line Items] | ||
| Number of Aircraft | 10 | 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Lessee, Operating Lease, Number Of Units No definition available. 
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