Note 5 - Acquisition - Allocation of Assets Acquired and Liabilities (Details) - Natural Habitat, Inc [Member] $ in Thousands	May 04, 2016 USD ($)
Cash and cash equivalents	$ 4,904
Prepaid expenses and other current assets	9,623
Property and equipment	2,068
Goodwill and other intangibles	28,305
Total assets	44,900
Accounts payable and accrued expenses	2,472
Unearned passenger revenues	15,000
Deferred tax liability	2,428
Noncontrolling interest in consolidated subsidiaries	4,975
Total liabilities	24,875
Total cash price paid upon acquisition and fair value of existing equity interest	$ 20,025