LONG-TERM DEBT (Details 2) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017	Mar. 31, 2017	Mar. 31, 2015
Long-term debt
Payments of Financing Costs		$ 17,729	$ 14,012
Outstanding borrowing amount	$ 1,374,611	1,374,611			$ 1,196,300
Transfer of Financial Assets Accounted for as Sales, Amount Derecognized	$ 0	0			78,006
Senior Notes Due 2025 [Member]
Long-term debt
Debt Instrument, Repurchase Obligation Due to Change of Control, Percentage of Original Principal	100.00%
Payments of Financing Costs	$ 8,779
Outstanding borrowing amount	500,000	500,000			0
Receivables Purchase Agreement [Member]
Long-term debt
Line of Credit Facility, Maximum Borrowing Capacity	90,000	90,000
Term loan credit agreement
Long-term debt
Outstanding borrowing amount	0	0			309,375
Revolving credit facility
Long-term debt
Line of Credit Facility, Maximum Borrowing Capacity	800,000	800,000		$ 850,000	1,000,000
Payments of Financing Costs		$ 633
Unamortized financing costs prior to amendment						$ 13,226
Debt Instrument, Description of Variable Rate Basis		LIBOR
Outstanding borrowing amount	50,000	$ 50,000			29,999
Letters of Credit Outstanding, Amount	30,152	30,152			27,240
Borrowing capacity under revolving credit facility after reductions for borrowings and letters of credit outstanding	719,848	719,848
Asset-backed Securities [Member]
Long-term debt
Line of Credit Facility, Maximum Borrowing Capacity	125,000	125,000		$ 225,000
Outstanding borrowing amount	$ 109,200	109,200			112,900
Program fee on the amount outstanding (as a percent)	0.13%
Line of Credit Facility, Commitment Fee Percentage	0.50%
Percentage of line of credit on which commitment fees are charged (as a percent)	100.00%
Capital Lease Obligations [Member]
Long-term debt
Outstanding borrowing amount	$ 58,297	58,297			72,800
Senior notes due 2021 [Member]
Long-term debt
Debt instrument principal amount					375,000
Outstanding borrowing amount	375,000	375,000			375,000
Notes Payable, Other Payables [Member]
Long-term debt
Outstanding borrowing amount	$ 0	$ 0			$ 7,978
Minimum [Member] | Receivables Purchase Agreement [Member]
Long-term debt
Program fee on the amount outstanding (as a percent)		0.65%
Minimum [Member] | Revolving credit facility
Long-term debt
Debt Instrument, Basis Spread on Variable Rate	1.50%
Maximum [Member] | Receivables Purchase Agreement [Member]
Long-term debt
Program fee on the amount outstanding (as a percent)		0.70%
Maximum [Member] | Revolving credit facility
Long-term debt
Debt Instrument, Basis Spread on Variable Rate	3.50%
Commitment fees (as a percent)	0.50%