Note 4 - Acquisitions (Details Textual) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Oct. 31, 2016	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Payments to Acquire Businesses, Net of Cash Acquired				$ 24,275
Goodwill		$ 40,323	$ 43,626	$ 40,323	$ 32,063
Cambrex High Point, Inc. [Member]
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Payments to Acquire Businesses, Net of Cash Acquired	$ 24,275
Goodwill	9,046
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	8,422
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	6,900
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	4,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities	4,400
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		$ 4,648
Cambrex High Point, Inc. [Member] | Selling, General and Administrative Expenses [Member]
Business Combination, Acquisition Related Costs	640
Business Combination, Integration Related Costs	$ 200