Note 12 - Segment Information - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Tour revenues	$ 81,238	$ 89,654
Tour revenues, change	$ (8,416)
Tour revenues, percentage change	(9.00%)
Operating income	$ 2,251	14,365
Operating income, change	$ (12,114)
Operating income, percentage change	(84.00%)
Depreciation and amortization	$ 6,690	6,188
Total depreciation and amortization, change	$ 502
Total depreciation and amortization, percentage change	8.00%
Assets	$ 705,522		$ 548,658
Intangibles, net	6,001		6,396
Goodwill	22,105		22,105
Lindblad Segment [Member]
Tour revenues	69,539	76,038
Tour revenues, change	$ (6,499)
Tour revenues, percentage change	(9.00%)
Operating income	$ 2,189	13,641
Operating income, change	$ (11,452)
Operating income, percentage change	(84.00%)
Depreciation and amortization	$ 6,248	5,794
Total depreciation and amortization, change	$ 454
Total depreciation and amortization, percentage change	8.00%
Assets	$ 625,876		471,499
Intangibles, net	3,144		3,325
Goodwill
Natural Habitat Segment [Member]
Tour revenues	11,699	13,616
Tour revenues, change	$ (1,917)
Tour revenues, percentage change	(14.00%)
Operating income	$ 62	724
Operating income, change	$ (662)
Operating income, percentage change	(91.00%)
Depreciation and amortization	$ 442	$ 394
Total depreciation and amortization, change	$ 48
Total depreciation and amortization, percentage change	12.00%
Assets	$ 79,646		77,159
Intangibles, net	2,857		3,071
Goodwill	$ 22,105		$ 22,105