Condensed Consolidated Statements of Comprehensive Income (Loss) - Parenthetical - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustment (CTA) gain (loss), tax	$ 5,985	$ 0	$ 5,985	$ 0
Net investment hedge CTA gain (loss), tax	0	0	1,637	0
Unrealized gain (loss) on available-for-sale securities, tax	0	29	0	(70)
Unrealized gain (loss) on cash flow hedges, tax	(11,758)	9,240	(10,398)	13,291
Net actuarial gain on defined benefit plans, tax	$ (4)	$ (4)	$ (10)	$ (10)

Amount of income tax expense (benefit) from transactions on foreign currency derivatives that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109240241&loc=d3e32211-110900

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

+ References

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 10A
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Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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