SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION CF (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 116,026	$ 253,226	$ 232,094
Capital expenditures	(372,375)	(601,834)	(628,613)
Acquisitions, net of cash received	0	(20,303)	(39,850)
Proceeds from sale of unconsolidated affiliate	0	4,185	112,210
Proceeds from asset dispositions	60,035	414,859	289,951
Investment in unconsolidated affiliate	(4,410)	0	0
Net cash used in investing activities	(316,750)	(203,093)	(266,302)
Proceeds from borrowings	928,802	454,393	533,064
Payments of contingent consideration	(9,453)	0	(6,000)
Debt issuance costs	(5,139)	0	(15,523)
Repayment of debt and debt redemption premiums	(677,003)	(460,274)	(512,492)
Proceeds from assignment of aircraft purchase agreements	0	0	106,113
Partial prepayment of put/call obligation	(55)	(59)	(57)
Acquisition of noncontrolling interests	(7,309)	(3,170)	(2,078)
Dividends paid to noncontrolling interest	(153)	0	0
Repurchase of Common Stock	0	(80,831)	(77,661)
Dividends paid	(38,076)	(45,078)	(36,320)
Increases (decreases) in cash related to intercompany advances and debt	0	0	0
Issuance of Common Stock	0	5,172	15,398
Tax benefit related to stock-based compensation	0	1,550	5,723
Net cash provided by (used in) financing activities	191,614	(128,297)	10,167
Effect of exchange rate changes on cash and cash equivalents	9,274	(22,031)	12,759
Net increase (decrease) in cash and cash equivalents	164	(100,195)	(11,282)
Cash and cash equivalents at beginning of period	104,146	204,341	215,623
Cash and cash equivalents at end of period	104,310	104,146	204,341
Parent Company Only
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(96,497)	(99,130)	(48,173)
Capital expenditures	(31,223)	(46,217)	(33,197)
Acquisitions, net of cash received		0	0
Proceeds from sale of unconsolidated affiliate		0	0
Proceeds from asset dispositions	0	0	0
Investment in unconsolidated affiliate	0
Net cash used in investing activities	(31,223)	(46,217)	(33,197)
Proceeds from borrowings	908,225	453,000	528,600
Payments of contingent consideration	0		0
Debt issuance costs	(5,139)		(15,523)
Repayment of debt and debt redemption premiums	(649,650)	(448,799)	(508,060)
Proceeds from assignment of aircraft purchase agreements			0
Partial prepayment of put/call obligation	(55)	(59)	(57)
Acquisition of noncontrolling interests	0	0	0
Dividends paid to noncontrolling interest	0
Repurchase of Common Stock		(80,831)	(77,661)
Dividends paid	(38,076)	(45,078)	(33,254)
Increases (decreases) in cash related to intercompany advances and debt	(52,470)	255,878	138,991
Issuance of Common Stock		5,172	15,398
Tax benefit related to stock-based compensation		1,550	5,723
Net cash provided by (used in) financing activities	162,835	140,833	54,157
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net increase (decrease) in cash and cash equivalents	35,115	(4,514)	(27,213)
Cash and cash equivalents at beginning of period	126	4,640	31,853
Cash and cash equivalents at end of period	35,241	126	4,640
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	104,989	245,451	107,059
Capital expenditures	(239,773)	(286,879)	(482,786)
Acquisitions, net of cash received		0	0
Proceeds from sale of unconsolidated affiliate		0	0
Proceeds from asset dispositions	50,780	211,423	284,042
Investment in unconsolidated affiliate	0
Net cash used in investing activities	(188,993)	(75,456)	(198,744)
Proceeds from borrowings	0	0	0
Payments of contingent consideration	0		0
Debt issuance costs	0		0
Repayment of debt and debt redemption premiums	0	0	0
Proceeds from assignment of aircraft purchase agreements			106,113
Partial prepayment of put/call obligation	0	0	0
Acquisition of noncontrolling interests	0	0	0
Dividends paid to noncontrolling interest	0
Repurchase of Common Stock		0	0
Dividends paid	0	0	34
Increases (decreases) in cash related to intercompany advances and debt	86,513	(169,111)	(19,832)
Issuance of Common Stock		0	0
Tax benefit related to stock-based compensation		0	0
Net cash provided by (used in) financing activities	86,513	(169,111)	86,315
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net increase (decrease) in cash and cash equivalents	2,509	884	(5,370)
Cash and cash equivalents at beginning of period	884	0	5,370
Cash and cash equivalents at end of period	3,393	884	0
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	107,534	106,459	173,654
Capital expenditures	(101,379)	(268,738)	(246,868)
Acquisitions, net of cash received		(20,303)	(39,850)
Proceeds from sale of unconsolidated affiliate		4,185	112,210
Proceeds from asset dispositions	9,255	203,436	140,147
Investment in unconsolidated affiliate	(4,410)
Net cash used in investing activities	(96,534)	(81,420)	(34,361)
Proceeds from borrowings	20,577	1,393	4,464
Payments of contingent consideration	(9,453)		(6,000)
Debt issuance costs	0		0
Repayment of debt and debt redemption premiums	(27,353)	(11,475)	(4,432)
Proceeds from assignment of aircraft purchase agreements			0
Partial prepayment of put/call obligation	0	0	0
Acquisition of noncontrolling interests	(7,309)	(3,170)	(2,078)
Dividends paid to noncontrolling interest	(153)
Repurchase of Common Stock		0	0
Dividends paid	0	0	(3,100)
Increases (decreases) in cash related to intercompany advances and debt	(34,043)	(86,767)	(119,159)
Issuance of Common Stock		0	0
Tax benefit related to stock-based compensation		0	0
Net cash provided by (used in) financing activities	(57,734)	(100,019)	(130,305)
Effect of exchange rate changes on cash and cash equivalents	9,274	(22,031)	12,759
Net increase (decrease) in cash and cash equivalents	(37,460)	(97,011)	21,747
Cash and cash equivalents at beginning of period	103,136	200,147	178,400
Cash and cash equivalents at end of period	65,676	103,136	200,147
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	446	(446)
Capital expenditures	0	0	134,238
Acquisitions, net of cash received		0	0
Proceeds from sale of unconsolidated affiliate		0	0
Proceeds from asset dispositions	0	0	(134,238)
Investment in unconsolidated affiliate	0
Net cash used in investing activities	0	0	0
Proceeds from borrowings	0	0	0
Payments of contingent consideration	0		0
Debt issuance costs	0		0
Repayment of debt and debt redemption premiums	0	0	0
Proceeds from assignment of aircraft purchase agreements			0
Partial prepayment of put/call obligation	0	0	0
Acquisition of noncontrolling interests	0	0	0
Dividends paid to noncontrolling interest	0
Repurchase of Common Stock		0	0
Dividends paid	0	0	0
Increases (decreases) in cash related to intercompany advances and debt	0	0	0
Issuance of Common Stock		0	0
Tax benefit related to stock-based compensation		0	0
Net cash provided by (used in) financing activities	0	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0	0
Net increase (decrease) in cash and cash equivalents	0	446	(446)
Cash and cash equivalents at beginning of period	0	(446)	0
Cash and cash equivalents at end of period	$ 0	$ 0	$ (446)