Note 5 - Property and Equipment, Net (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Depreciation, Total	$ 5,492	$ 5,044
Capitalized Computer Software, Gross	6,916		$ 6,879
Capitalized Computer Software, Amortization	99	$ 186
Capital Expenditures Incurred but Not yet Paid	$ 1,944		$ 2,580

Future cash outflow to pay for purchases of fixed assets that have occurred.

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Amount of expense for amortization of capitalized computer software costs.

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