Derivative Instruments and Hedging Activities Open Foreign Currency Contracts (Details) - Cash Flow Hedging - Foreign Exchange Contract - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Derivative [Line Items]
Notional Amounts (in U.S. Dollars)	$ 159,575	$ 74,355
Net Unrealized Gain (Loss)	964	3,128
Australian Dollar
Derivative [Line Items]
Notional Amounts (in U.S. Dollars)	8,695	0
Net Unrealized Gain (Loss)	288	0
Canadian Dollar
Derivative [Line Items]
Notional Amounts (in U.S. Dollars)	136,559	55,133
Net Unrealized Gain (Loss)	33	2,564
Mexican Peso
Derivative [Line Items]
Notional Amounts (in U.S. Dollars)	14,321	19,222
Net Unrealized Gain (Loss)	$ 643	$ 564