Derivative Financial Instruments - Outstanding Foreign Currency Forward Contracts that were Entered into to Hedge Forecasted Cash Flows (Details) - Jun. 30, 2017 € in Millions, ₩ in Millions, ¥ in Millions, £ in Millions	EUR (€)	GBP (£)	JPY (¥)	KRW (₩)
Foreign Exchange Contract
Derivative [Line Items]
Notional Amount	€ 59.6	£ 3.1	¥ 1,496.5	₩ 10,635.8