Note 4 - Purchased Intangible Assets and Goodwill - Changes in Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill, beiginning balance	$ 169,553	$ 169,553
Accumulated impairment losses, beiginning balance	(85,141)	(85,141)
Net beginning balance, beiginning balance	84,412	84,412
Impairment	(45,981)
Goodwill, ending balance	169,553	169,553
Accumulated impairment losses, ending balance	(131,122)	(85,141)
Net ending balance, ending balance	38,431	84,412
U.S. and Canada Segment [Member]
Goodwill, beiginning balance	43,872	43,872
Accumulated impairment losses, beiginning balance	(5,441)	(5,441)
Net beginning balance, beiginning balance	38,431	38,431
Impairment
Goodwill, ending balance	43,872	43,872
Accumulated impairment losses, ending balance	(5,441)	(5,441)
Net ending balance, ending balance	38,431	38,431
Latin America Segment [Member]
Goodwill, beiginning balance	125,681	125,681
Accumulated impairment losses, beiginning balance	(79,700)	(79,700)
Net beginning balance, beiginning balance	45,981	45,981
Impairment	(45,981)
Goodwill, ending balance	125,681	125,681
Accumulated impairment losses, ending balance	(125,681)	(79,700)
Net ending balance, ending balance		$ 45,981