Fair Value Measurements - Assets and Liabilities Measured at Fair Value (Details) - Recurring - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Assets
Mutual funds	$ 168,693	$ 142,408
Derivative financial instruments	8,425	6,030
Total	177,118	148,438
Liabilities
Derivative financial instruments	3,289	6,279
Total	3,289	6,279
Level 1
Assets
Mutual funds	168,693	142,408
Derivative financial instruments	0	0
Total	168,693	142,408
Liabilities
Derivative financial instruments	0	0
Total	0	0
Level 2
Assets
Mutual funds	0	0
Derivative financial instruments	8,425	6,030
Total	8,425	6,030
Liabilities
Derivative financial instruments	3,289	6,279
Total	3,289	6,279
Level 3
Assets
Mutual funds	0	0
Derivative financial instruments	0	0
Total	0	0
Liabilities
Derivative financial instruments	0	0
Total	$ 0	$ 0

Money market and mutual fund fair value disclosure.

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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- References

No definition available.

+ Details

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

+ Details

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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- References

No definition available.

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