Accumulated Other Comprehensive Income (Loss) - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net increase in other comprehensive income (loss)	$ 21,292	$ 42,637
Currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net increase in other comprehensive income (loss)	$ 14,133	$ 41,989

Amount after tax of other comprehensive income (loss) attributable to parent entity.

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