Foreign Currency Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Foreign Currency Derivatives [Abstract]

Schedule of gains (losses) on foreign currency forward contracts

The net losses on foreign currency forward contracts included in “foreign currency exchange loss, net” in the consolidated statements of operations are as follows (in thousands):

	Year Ended December 31,
	2017		2016			2015
Total loss	$	—	$	(88	)	$	(720	)

Schedule of foreign currency gains (losses) on underlying assets and liabilities

The net foreign currency gains or losses on those underlying monetary assets and liabilities included in “foreign currency exchange loss, net” in the consolidated statements of operations are as follows (in thousands):

	Year Ended December 31,
	2017		2016			2015
Total gain (loss)	$	—	$	(37	)	$	179