Hedging - Offsetting Derivatives (Details) - Foreign currency forward contracts - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Offsetting Derivative Assets [Abstract]
Gross Amounts Recognized	$ 20,537	$ 13
Gross Amounts Offset	0	0
Gross Amounts Presented	20,537	13
Gross Amounts Not Offset	(448)	(13)
Legal Offset	20,089	0
Offsetting Derivative Liabilities [Abstract]
Gross Amounts Recognized	(448)	(14,508)
Gross Amounts Offset	0	0
Gross Amounts Presented	(448)	(14,508)
Gross Amounts Not Offset	448	13
Legal Offset	$ 0	$ (14,495)

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