Derivative Financial Instruments and Hedging Activities - Notional Amounts of Outstanding Positions (Details) $ in Thousands, $ in Millions	Dec. 31, 2018 USD ($)	Mar. 31, 2018 NZD ($)	Dec. 31, 2017 USD ($)
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Notional Amount		$ 37
Designated as Hedging Instrument | Cash Flow Hedging | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Notional Amount	$ 69,950		$ 107,400
Designated as Hedging Instrument | Cash Flow Hedging | Foreign currency option contracts
Derivatives, Fair Value [Line Items]
Notional Amount	24,000		48,000
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swaps
Derivatives, Fair Value [Line Items]
Notional Amount	650,000		650,000
Not Designated as Hedging Instrument | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Notional Amount	9,396		18,439
Not Designated as Hedging Instrument | Carbon options
Derivatives, Fair Value [Line Items]
Notional Amount	$ 2,517		$ 0