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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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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2018
New Accounting Pronouncement, Early Adoption [Line Items]
Cash provided by operating activities	$ 23,880	$ 44,156
Cash used in investing activities	$ 800,495	(124,923)
Accounting Standards Update 2016-18 and Accounting Standards Update 2016-15
New Accounting Pronouncement, Early Adoption [Line Items]
Cash provided by operating activities		44,156
Cash used in investing activities		(124,923)
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 provided by operating activities		45,864
Cash used in investing activities		(126,693)
Effect of Change \| Accounting Standards Update 2016-18 and Accounting Standards Update 2016-15
New Accounting Pronouncement, Early Adoption [Line Items]
Cash provided by operating activities		(1,708)
Cash used in investing activities		$ 1,770