Foreign Currency Contracts - Additional Information (Details) - Foreign Currency Forward Contracts - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Notional amount of foreign currency forward contracts	$ 31.2	$ 17.9
Net gain (loss) on foreign currency forward contracts	(0.2)	0.2
Foreign Exchange Transaction Gains (Losses)
Derivative [Line Items]
Aggregate net gain recognized	$ 1.5	$ 0.2

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Fair value as of the balance sheet date of all foreign currency derivatives not designated as hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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