Guarantor Subsidiaries Financial Information - Condensed Cash Flow Statement (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Condensed Financial Statements, Captions [Line Items]
Net cash (used for) provided by operating activities	$ 38,038	$ 26,511
Net cash used for investing activities	(104,160)	(905,872)
Net cash provided by (used for) financing activities	1,995,310	(70,049)
Effect of changes in currency exchange rates	(27,208)	34,258
Increase (decrease) in cash	1,901,980	(915,152)
Cash, cash equivalents, and restricted cash, beginning of period	233,401	1,143,232
Cash, cash equivalents, and restricted cash, end of period	2,135,381	228,080
Elimination
Condensed Financial Statements, Captions [Line Items]
Net cash (used for) provided by operating activities	(73,872)	(26,405)
Net cash used for investing activities	0	0
Net cash provided by (used for) financing activities	73,872	26,405
Effect of changes in currency exchange rates	0	0
Increase (decrease) in cash	0	0
Cash, cash equivalents, and restricted cash, beginning of period	0	0
Cash, cash equivalents, and restricted cash, end of period	0	0
Parent
Condensed Financial Statements, Captions [Line Items]
Net cash (used for) provided by operating activities	(111,120)	(38,959)
Net cash used for investing activities	(12,498)	(12,591)
Net cash provided by (used for) financing activities	1,883,490	52,077
Effect of changes in currency exchange rates	0	0
Increase (decrease) in cash	1,759,872	527
Cash, cash equivalents, and restricted cash, beginning of period	933	2,522
Cash, cash equivalents, and restricted cash, end of period	1,760,805	3,049
Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash (used for) provided by operating activities	95,503	101,597
Net cash used for investing activities	(1,303)	(2,358)
Net cash provided by (used for) financing activities	(94,752)	(99,615)
Effect of changes in currency exchange rates	0	0
Increase (decrease) in cash	(552)	(376)
Cash, cash equivalents, and restricted cash, beginning of period	625	1,226
Cash, cash equivalents, and restricted cash, end of period	73	850
Non-Guarantors
Condensed Financial Statements, Captions [Line Items]
Net cash (used for) provided by operating activities	127,527	(9,722)
Net cash used for investing activities	(90,359)	(890,923)
Net cash provided by (used for) financing activities	132,700	(48,916)
Effect of changes in currency exchange rates	(27,208)	34,258
Increase (decrease) in cash	142,660	(915,303)
Cash, cash equivalents, and restricted cash, beginning of period	231,843	1,139,484
Cash, cash equivalents, and restricted cash, end of period	$ 374,503	$ 224,181

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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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) from financing activities, including 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) from investing activities, including 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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