SUBSEQUENT EVENTS (Details) (USD $)	1 Months Ended	3 Months Ended		1 Months Ended		3 Months Ended
	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Apr. 30, 2015	Jun. 30, 2015	Jun. 30, 2011
Subsequent Event [Line Items]
Debt purchased, amount	$ 506,366,000		$ 506,366,000
Interest rate							6.50%
Debt issued, amount							500,000,000
Total consideration paid for debt	579,659,000	145,918,000	579,676,000
Premium paid for purchase of debt	71,829,000		71,829,000
Transaction cost related to termination of debt			1,464,000
Debt to EBITDA ratio		3.5
Ebitda To Net Cash Interest Expense		3.0
6.50% notes due 2016 [Member]
Subsequent Event [Line Items]
Debt purchased, amount	374,999,000		374,999,000
Interest rate	6.50%	6.50%	6.50%	6.50%
Maturity year		2016	2016
6.40% notes due 2017 [Member]
Subsequent Event [Line Items]
Debt purchased, amount	131,367,000		131,367,000
Interest rate	6.40%	6.40%	6.40%	6.40%
Maturity year		2017	2017
7.00% notes due 2018 [Member]
Subsequent Event [Line Items]
Debt purchased, amount		127,303,000		127,303,000
Interest rate		7.00%		7.00%
Maturity year		2018		2018
Total consideration paid for debt		145,899,000
Premium paid for purchase of debt		18,140,000		18,140,000
Transaction cost related to termination of debt		456,000
8.85% notes due 2021 [Member]
Subsequent Event [Line Items]
Interest rate		8.85%		8.85%
Maturity year		2021
Industrial revenue bonds [Member]
Subsequent Event [Line Items]
Maturity year		2022
4.50% notes due 2025 [Member]
Subsequent Event [Line Items]
Interest rate		4.50%		4.50%
Maturity year		2025
Debt issued, amount		400,000,000		400,000,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Debt purchased, amount					343,819,000
Total consideration paid for debt					384,990,000
Premium paid for purchase of debt					41,153,000
Transaction cost related to termination of debt					18,000
Interest expense						45,303,000
Net cost/benefit associated with the acceleration of a proportional amount of unamortized discounts, deferred gains, deferred financing costs and amounts accumulated in OCI					4,132,000
Subsequent Event [Member] | 6.50% notes due 2016 [Member]
Subsequent Event [Line Items]
Debt purchased, amount					125,001,000
Interest rate					6.50%
Maturity year					2016
Subsequent Event [Member] | 6.40% notes due 2017 [Member]
Subsequent Event [Line Items]
Debt purchased, amount					218,633,000
Interest rate					6.40%
Maturity year					2017
Subsequent Event [Member] | 7.00% notes due 2018 [Member]
Subsequent Event [Line Items]
Debt purchased, amount					$ 185,000
Interest rate					7.00%
Maturity year					2018