Note 10 - Collaboration and License Agreements (Details) - Cash Streams And Related Revenue Recognized Or Deferred Under Takeda Agreement (Takeda [Member], USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013		Dec. 31, 2012
Development Milestone [Member] | Research And Development Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Cash Received	$ 10,000
Revenue Recognized	10,000
Change in Accounts Receivable		[1]
Reimbursement Of Research And Development Expenses [Member] | Research And Development Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Amount Deferred	314		249
Cash Received	8,010
Revenue Recognized	6,288
Change in Accounts Receivable	(1,657)	[1]
Collaborative Arrangement [Member]
Deferred Revenue Arrangement [Line Items]
Amount Deferred	1,066		1,176
Revenue Recognized	110
Change in Accounts Receivable		[1]
Up Front Payment Remainder [Member]
Deferred Revenue Arrangement [Line Items]
Change in Accounts Receivable		[1]
Research And Development Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Amount Deferred	314		249
Cash Received	18,010
Revenue Recognized	16,288
Change in Accounts Receivable	(1,657)	[1]
Product Royalty Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Cash Received	37,852
Revenue Recognized	37,271
Change in Accounts Receivable	(581)	[1]
Co-promotion revenue [Member]
Deferred Revenue Arrangement [Line Items]
Cash Received	839
Revenue Recognized	61
Change in Accounts Receivable	$ (778)	[1]

[1] Includes billed and unbilled accounts receivable.