GUARANTOR SUBSIDIARIES FINANCIAL INFORMATION - Condensed Cash Flow Statement (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	$ 188,811	$ 450,530	$ 450,844
Net cash used in investing activities	(275,729)	(775,065)	(380,136)
Net cash provided by (used in) financing activities	(97,431)	522,971	(251,498)
Effect of changes in currency exchange rates	19,266	(26,143)	(18,868)
(Decrease) increase in cash	(165,083)	172,293	(199,658)
Cash, beginning of year	398,484	226,191	425,849
Cash, end of year	233,401	398,484	226,191
Elimination
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	(34,028)	(42,138)	(81,787)
Net cash used in investing activities	0	0	0
Net cash provided by (used in) financing activities	34,028	42,138	81,787
Effect of changes in currency exchange rates	0	0	0
(Decrease) increase in cash	0	0	0
Cash, beginning of year	0	0	0
Cash, end of year	0	0	0
Parent
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	(49,231)	(44,611)	(90,374)
Net cash used in investing activities	(11,156)	(829,783)	(7,862)
Net cash provided by (used in) financing activities	58,798	876,916	(48,570)
Effect of changes in currency exchange rates	0	0	0
(Decrease) increase in cash	(1,589)	2,522	(146,806)
Cash, beginning of year	2,522	0	146,806
Cash, end of year	933	2,522	0
Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	249,204	332,822	487,516
Net cash used in investing activities	(120,661)	(14,725)	(109,326)
Net cash provided by (used in) financing activities	(133,237)	(321,758)	(378,330)
Effect of changes in currency exchange rates	0	0	0
(Decrease) increase in cash	(4,694)	(3,661)	(140)
Cash, beginning of year	9,496	13,157	13,297
Cash, end of year	4,802	9,496	13,157
Non-Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	22,866	204,457	135,489
Net cash used in investing activities	(143,912)	69,443	(262,948)
Net cash provided by (used in) financing activities	(57,020)	(74,325)	93,615
Effect of changes in currency exchange rates	19,266	(26,143)	(18,868)
(Decrease) increase in cash	(158,800)	173,432	(52,712)
Cash, beginning of year	386,466	213,034	265,746
Cash, end of year	$ 227,666	$ 386,466	$ 213,034

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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