Derivatives - Forward Notional Contracts (Details) - Sep. 30, 2017 - Foreign currency forward contracts € in Thousands, ₩ in Thousands, ¥ in Thousands, ¥ in Thousands, £ in Thousands, SGD in Thousands, SFr in Thousands, SEK in Thousands, MXN in Thousands, HKD in Thousands, DKK in Thousands, CAD in Thousands, BRL in Thousands, AUD in Thousands	CNY (¥)	MXN	CHF (SFr)	KRW (₩)	GBP (£)	CAD	JPY (¥)	SGD	SEK	EUR (€)	HKD	BRL	AUD	DKK
Not designated as hedging instrument
Derivative [Line Items]
Notional amount of derivative	¥ 39,954	MXN 17,537	SFr 278	₩ 1,800,000	£ 1,128	CAD 1,968	¥ 178,500	SGD 3,585	SEK 6,007	€ 21,801	HKD 11,000	BRL 8,500	AUD 4,599
Derivatives designated as cash flow hedges | Designated as hedging instrument
Derivative [Line Items]
Notional amount of derivative		MXN 64,425	SFr 1,088		£ 2,550				SEK 10,805	€ 5,555				DKK 7,775