Note 6 - Accumulated Other Comprehensive Loss - Disclosure of Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Balance	$ 1,032,851		$ 761,261
Balance	1,023,687		809,955
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	(16,622)		(18,832)
Other comprehensive loss before reclassifications	(33,214)	[1]	(933)
Amounts reclassified from AOCL	0		0
Net current-period other comprehensive loss	(33,214)		(933)
Balance	(49,836)		(19,765)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	0		(10,541)
Other comprehensive loss before reclassifications	0		0
Amounts reclassified from AOCL	0		0
Net current-period other comprehensive loss	0		0
Balance	0		(10,541)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Balance	(8,295)		5,560
Other comprehensive loss before reclassifications	(15,813)	[2]	(5,124)	[3]
Amounts reclassified from AOCL	0		0
Net current-period other comprehensive loss	(15,813)		(5,124)
Balance	(24,108)		436
AOCI Attributable to Parent [Member]
Balance	(24,917)		(23,813)
Other comprehensive loss before reclassifications	(49,027)		(6,057)
Amounts reclassified from AOCL	0		0
Net current-period other comprehensive loss	(49,027)		(6,057)
Balance	$ (73,944)		$ (29,870)

[1] Represents the unfavorable impact from the strengthening of the U.S. dollar against foreign currencies during the three months ended March 31, 2020, particularly the Mexican Peso, Euro, Brazilian Real, and Russian Ruble.

[2] Represents unrealized losses of $(21,154), net of tax effect of $5,341 for the three months ended March 31, 2020.

[3] Represents unrealized losses of $(6,924), net of tax effect of $1,800 for the three months ended March 31, 2019.