Basis of Presentation and Summary of Significant Accounting Policies (Details 3) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities	$ 302,926	$ 295,149
Net cash used in investing activities	239,122	(275,885)
Net Cash Provided by (Used in) Financing Activities	$ (580,290)	(16,818)
As Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities		285,025
Net cash used in investing activities		(274,139)
Net Cash Provided by (Used in) Financing Activities		(16,449)
Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities		10,124
Net cash used in investing activities		(1,746)
Net Cash Provided by (Used in) Financing Activities		$ (369)