LONG-TERM DEBT (Details 3) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	May 03, 2021	Sep. 23, 2019	Jun. 30, 2019	Mar. 31, 2019
Long-term debt
Interest Paid, Including Capitalized Interest, Operating and Investing Activities			$ 60,885	$ 63,261
Payments of Financing Costs			17,545	$ 1,941
Long-term debt	$ 1,408,688		1,408,688					$ 1,488,821
Revolving credit facility
Long-term debt
Line of Credit Facility, Maximum Borrowing Capacity	700,000		700,000		$ 406,500
Payments of Financing Costs		$ 6,944
Deferred Finance Costs, Noncurrent, Net						$ 6,222
Letters of Credit Outstanding, Amount	22,338		22,338					30,773
Line of Credit Facility, Remaining Borrowing Capacity	581,329		581,329
Long-term debt	0		0					215,000
Asset-backed Securities [Member]
Long-term debt
Line of Credit Facility, Maximum Borrowing Capacity	$ 75,000		75,000					125,000
Line of Credit Facility, Commitment Fee Percentage	0.50%
Line of Credit, Commitment Fee on Maximum Amount Available, Percentage	100.00%
Line of Credit Facility, Amount Outstanding Commitment Fee, Percentage	0.13%
Long-term debt	$ 75,000		75,000					80,700
Equipment leasing facility and other capital leases
Long-term debt
Long-term debt	$ 25,967		$ 25,967					31,292
Senior Notes Due 2024 [Member] [Member]
Long-term debt
Debt instrument interest rate stated percentage (as a percent)	6.25%		6.25%
Payments of Financing Costs			$ 9,300
Effective interest yield on principal amount (as a percent)	6.25%		6.25%
Long-term debt	$ 525,000		$ 525,000					0
Senior notes due 2021 [Member]
Long-term debt
Debt instrument principal amount							$ 375,000
Debt instrument interest rate stated percentage (as a percent)							4.875%
Long-term debt	$ 0		$ 0					375,000
Senior Notes Due 2022 [Member]
Long-term debt
Debt instrument interest rate stated percentage (as a percent)	5.25%		5.25%
Proceeds from loan, percentage of principal (as a percent)	100.00%
Effective interest yield on principal amount (as a percent)	5.25%		5.25%
Long-term debt	$ 300,000		$ 300,000					300,000
Senior Notes Due 2025 [Member]
Long-term debt
Debt instrument interest rate stated percentage (as a percent)	7.75%		7.75%
Long-term debt	$ 500,000		$ 500,000					500,000
Estimate of Fair Value Measurement [Member]
Long-term debt
Long-term debt	1,467,892		1,467,892					1,568,037
Reported Value Measurement [Member]
Long-term debt
Long-term debt	$ 1,408,688		$ 1,408,688					$ 1,488,821
Maximum [Member] | Revolving credit facility
Long-term debt
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.50%
LIBOR | Minimum [Member] | Revolving credit facility
Long-term debt
Debt Instrument, Basis Spread on Variable Rate	1.50%
LIBOR | Maximum [Member] | Revolving credit facility
Long-term debt
Debt Instrument, Basis Spread on Variable Rate	3.50%