Market Risks and Derivative Contracts Market Risks and Derivative Contracts (Tables)

9 Months Ended

Sep. 30, 2017

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Notional Amounts of Outstanding Derivative Positions Table

Derivative Contracts	US Dollar Notional Amount		Traded Exchange Rate	Settlement Date
	(In Thousands)
Forward sale Mexican peso	$	5,088	17.93	10/18/2017

Derivatives Designated as Hedging Instruments Table

Foreign currency derivative instruments	Balance Sheet	Fair Value at
	Location	September 30, 2017		December 31, 2016
		(In Thousands)
Forward sale contracts	Current assets	$	92	$	57
Forward sale contracts	Current liabilities	—		—
Net asset		$	92	$	57