Derivatives - Forward Notional Contracts (Details) - Foreign currency forward contract € in Thousands, ₩ in Thousands, ¥ in Thousands, ¥ in Thousands, £ in Thousands, kr in Thousands, kr in Thousands, kr in Thousands, SFr in Thousands, R$ in Thousands, R in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands	Sep. 30, 2019 ZAR (R) DerivativeInstrument	Sep. 30, 2019 SGD ($) DerivativeInstrument	Sep. 30, 2019 JPY (¥) DerivativeInstrument	Sep. 30, 2019 CHF (SFr) DerivativeInstrument	Sep. 30, 2019 BRL (R$) DerivativeInstrument	Sep. 30, 2019 DKK (kr) DerivativeInstrument	Sep. 30, 2019 EUR (€) DerivativeInstrument	Sep. 30, 2019 SEK (kr) DerivativeInstrument	Sep. 30, 2019 KRW (₩) DerivativeInstrument	Sep. 30, 2019 HKD ($) DerivativeInstrument	Sep. 30, 2019 CAD ($) DerivativeInstrument	Sep. 30, 2019 AUD ($) DerivativeInstrument	Sep. 30, 2019 NOK (kr) DerivativeInstrument	Sep. 30, 2019 CNY (¥) DerivativeInstrument	Sep. 30, 2019 GBP (£) DerivativeInstrument	Sep. 30, 2019 MXN ($) DerivativeInstrument
Designated as hedging instrument | Derivatives designated as cash flow hedges
Derivative [Line Items]
Average number of contracts entered into per month	150	150	150	150	150	150	150	150	150	150	150	150	150	150	150	150
Notional amount of derivative			¥ 1,190,000	SFr 3,780	R$ 7,830	kr 32,225	€ 33,150	kr 43,450	₩ 7,000,000		$ 6,495	$ 5,930	kr 14,050	¥ 408,000	£ 7,315	$ 453,500
Not designated as hedging instrument
Derivative [Line Items]
Average number of contracts entered into per month	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20
Notional amount of derivative	R 40,218	$ 600	¥ 1,380,856	SFr 739	R$ 13,000	kr 4,072	€ 1,225	kr 12,647	₩ 7,343,000	$ 11,000	$ 1,795	$ 12,695	kr 2,999	¥ 69,069	£ 6,982	$ 35,000