Derivative Financial Instruments (Tables)

3 Months Ended

Mar. 31, 2018

Derivative Financial Instruments

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

	March 31, 2018					December 31, 2017
	Fair		Maturity	Notional		Fair		Maturity	Notional
	Value		Dates	Amounts		Value		Dates	Amounts
	(in thousands)
Foreign currency exchange forwards	$	—	April 2018	$	5,062	$	—	January 2018	$	622

Schedule of gains and (losses) and weighted average notional amount of derivatives

	Three months ended March 31, 2018				Three months ended March 31, 2017
			Weighted average				Weighted average
	Gains (losses)		notional amount		Gains (losses)		notional amount
	(in thousands)
Foreign currency exchange forwards	$	17	$	930	$	—	$	—