Hedging - Offsetting Derivatives (Details) - Cash flow hedging - Foreign currency forward contracts - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Offsetting Derivative Assets [Abstract]
Gross Amounts Recognized	$ 13,529	$ 20,537
Offsetting Derivative Liabilities [Abstract]
Gross Amounts Recognized	(968)	(448)
Designated as hedging instruments
Offsetting Derivative Assets [Abstract]
Gross Amounts Recognized	13,529	20,537
Gross Amounts Offset	0	0
Gross Amounts Presented	13,529	20,537
Gross Amounts Not Offset	(968)	(448)
Legal Offset	12,561	20,089
Offsetting Derivative Liabilities [Abstract]
Gross Amounts Recognized	(968)	(448)
Gross Amounts Offset	0	0
Gross Amounts Presented	(968)	(448)
Gross Amounts Not Offset	968	448
Legal Offset	$ 0	$ 0

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