FAIR VALUE DISCLOSURES - Fair Value of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Mar. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	$ 1,329,370	$ 1,293,364
Fair value of total debt	1,208,910	1,215,065
6¼% Senior Notes due 2022 | Senior Notes Due 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	401,535	401,535
Fair value of total debt	281,075	323,236
Term Loan
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	150,835	261,907
Fair value of total debt	150,835	261,907
Term Loan Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	28,929	45,900
Fair value of total debt	28,929	45,900
Revolving Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	89,100	139,100
Fair value of total debt	89,100	139,100
Secured Debt | Lombard Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	207,153	196,832
Fair value of total debt	207,153	196,832
Secured Debt | Macquarie Credit Agreement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	192,028	200,000
Fair value of total debt	192,028	200,000
Secured Debt | PK Air Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	230,000	0
Fair value of total debt	230,000	0
Other Debt | Airnorth debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	15,193	16,471
Fair value of total debt	15,193	16,471
Other Debt | Eastern Airways debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	14,597	15,326
Fair value of total debt	14,597	15,326
Other Debt | Other Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Carrying value of total debt	0	16,293
Fair value of total debt	$ 0	$ 16,293