DEBT (Debt) (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016
Debt Instrument [Line Items]
Total short-term debt		$ 0		$ 0	$ 0
Total long-term debt - face value		3,369,058		2,004,065	2,004,189
Unamortized discounts and debt issuance costs		(33,989)		(21,176)	(21,531)
Total long-term debt - book value		3,335,069		1,982,889	1,982,658
Less current maturities	[1]	525,776		138	131
Total long-term debt - reported value		2,809,293		1,982,751	1,982,527
Estimated fair value of long-term debt		3,077,069		2,243,213	2,272,149
Notes due 2018 [Member]
Debt Instrument [Line Items]
Less current maturities		522,500
Bank Line of Credit [Member]
Debt Instrument [Line Items]
Total short-term debt	[2],[3],[4]	$ 0		0	0
Maturity date		Dec. 31, 2021
Bank Line of Credit [Member]
Debt Instrument [Line Items]
Total long-term debt - face value	[2],[3],[4]	$ 0		235,000	235,000
Maturity date		Dec. 31, 2021
Notes [Member] | 7.00% notes due 2018 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 272,512		272,512	272,512
Interest rate		7.00%
Maturity year		2018
Effective interest rate		7.87%
Notes [Member] | 10.375% notes due 2018 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 250,000		250,000	250,000
Interest rate		10.375%
Maturity year		2018
Effective interest rate		10.63%
Notes [Member] | Floating-Rate Notes Due 2020 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 250,000		0	0
Maturity year		2020
Effective interest rate		2.05%
Notes [Member] | 7.50% notes due 2021 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 600,000		600,000	600,000
Interest rate		7.50%
Maturity year		2021
Effective interest rate		7.75%
Notes [Member] | 8.85% notes due 2021 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 6,000		6,000	6,000
Interest rate		8.85%
Maturity year		2021
Effective interest rate		8.88%
Notes [Member] | Delayed draw term loan [Member]
Debt Instrument [Line Items]
Total long-term debt - face value	[3],[4]	$ 250,000		0	0
Maturity year		2021
Effective interest rate	[3],[4]	2.41%
Notes [Member] | 4.50% notes due 2025 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 400,000		400,000	400,000
Interest rate		4.50%
Maturity year		2025
Effective interest rate		4.65%
Notes [Member] | 3.90% notes due 2027 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 400,000		0	0
Interest rate		3.90%	3.90%
Maturity year		2027
Effective interest rate		4.00%
Notes [Member] | 7.15% notes due 2037 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 240,188		240,188	240,188
Interest rate		7.15%
Maturity year		2037
Effective interest rate		8.05%
Notes [Member] | 4.50% notes due 2047 [Member]
Debt Instrument [Line Items]
Total long-term debt - face value		$ 700,000		0	0
Interest rate		4.50%
Maturity year		2047
Effective interest rate		4.59%
Other Notes [Member]
Debt Instrument [Line Items]
Total long-term debt - face value	[3]	$ 358		$ 365	$ 489
Effective interest rate	[3]	6.31%

[1] Current maturities as of June 30, 2017 includes $522.5 million of notes due in 2018 which were early retired in July 2017 as discussed below within the Term Debt caption.

[2] Borrowings on the bank line of credit are classified as short-term debt if we intend to repay within twelve months and as long-term debt otherwise.

[3] Non-publicly traded debt.

[4] The effective interest rate is the spread over LIBOR as of the most recent balance sheet date.