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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 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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No definition available.

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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018
New Accounting Pronouncement, Early Adoption [Line Items]
Cash used in operating activities	$ (371)	$ (4,001)
Cash used in investing activities	$ 751,619	(199,989)
Accounting Standards Update 2016-18 and Accounting Standards Update 2016-15
New Accounting Pronouncement, Early Adoption [Line Items]
Cash used in operating activities		(4,001)
Cash used in investing activities		(199,989)
Accounting Standards Update 2016-01 \| Cumulative other comprehensive loss
New Accounting Pronouncement, Early Adoption [Line Items]
Cumulative effect of new accounting principle in period of adoption			$ (1,902)
Accounting Standards Update 2016-01 \| Cumulative net income
New Accounting Pronouncement, Early Adoption [Line Items]
Cumulative effect of new accounting principle in period of adoption			$ 1,902
Originally Reported \| Accounting Standards Update 2016-18 and Accounting Standards Update 2016-15
New Accounting Pronouncement, Early Adoption [Line Items]
Cash used in operating activities		(2,690)
Cash used in investing activities		(200,923)
Effect of Change \| Accounting Standards Update 2016-18 and Accounting Standards Update 2016-15
New Accounting Pronouncement, Early Adoption [Line Items]
Cash used in operating activities		(1,311)
Cash used in investing activities		$ 934