Other (Income) Expense Foreign Currency Gain Loss by Currency (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	$ 2,598	$ 951	$ 1,776
Angolan Kwanza Spot [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	202	(3)	408
Australian Dollar [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	183	12	136
British Pound [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	158	(92)	807
Canadian Dollar [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	458	(62)	(130)
Euro [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	208	1,413	(49)
Indonesian Rupiah [Member] [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	297	80	29
Mexican Peso [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	141	23	(47)
Turkish Lira [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	300	32	93
Other Currencies Net [Member]
Foreign Currency Fair Value Hedge Derivative [Line Items]
Gain (loss) by currency	$ 651	$ (452)	$ 529