Derivative Financial Instruments - Summary of Outstanding Foreign Currency Forward Contracts (Details) - Foreign Currency Forward Contracts	12 Months Ended
	Dec. 31, 2017 USD ($) € / £ € / $ £ / $ $ / ¥ $ / ¥ $ / TWD	Dec. 31, 2016 USD ($)
Derivative [Line Items]
Notional Amount	$ 87,600,000	$ 0
Derivative One | Cash Flow Hedges | Non-designated
Derivative [Line Items]
Notional Amount	$ 2,494,000
Effective Date	Dec. 31, 2017
Maturity Date	Dec. 31, 2017
Index	EUR/GPB
Weighted Average Strike Rate | € / £	1.2009
Derivative Two | Cash Flow Hedges | Non-designated
Derivative [Line Items]
Notional Amount	$ 10,514,000
Effective Date	Dec. 31, 2017
Maturity Date	Dec. 31, 2017
Index	EUR/USD
Weighted Average Strike Rate | € / $	1.2009
Derivative Three | Cash Flow Hedges | Non-designated
Derivative [Line Items]
Notional Amount	$ 10,612,000
Effective Date	Dec. 31, 2017
Maturity Date	Dec. 31, 2017
Index	GPB/USD
Weighted Average Strike Rate | £ / $	1.3541
Derivative Four | Cash Flow Hedges | Non-designated
Derivative [Line Items]
Notional Amount	$ 31,834,000
Effective Date	Dec. 31, 2017
Maturity Date	Dec. 31, 2017
Index	USD/CNY
Weighted Average Strike Rate | $ / ¥	6.5343
Derivative Five | Cash Flow Hedges | Non-designated
Derivative [Line Items]
Notional Amount	$ 1,594,000
Effective Date	Dec. 31, 2017
Maturity Date	Dec. 31, 2017
Index	USD/JPY
Weighted Average Strike Rate | $ / ¥	112.35
Derivative Six | Cash Flow Hedges | Non-designated
Derivative [Line Items]
Notional Amount	$ 30,594,000
Effective Date	Dec. 31, 2017
Maturity Date	Dec. 31, 2017
Index	USD/TWD
Weighted Average Strike Rate | $ / TWD	29.406