Fair Value Measurements and Disclosures - Notional Amounts and Fair Values of Outstanding Derivative Instruments (Details) - Forward Foreign Currency Contracts [Member] - Not Designated as Hedging Instrument [Member] - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Purchase [Member]
Derivatives Fair Value [Line Items]
Notional Amount	$ 21,600,000	$ 12,600,000
Fair Value Asset	0	0
Fair Value Liability	100,000	0
Sell [Member]
Derivatives Fair Value [Line Items]
Notional Amount	16,600,000	1,300,000
Fair Value Asset	0	0
Fair Value Liability	$ 100,000	$ 0