Note 11 - Long-Term Debt Interest Expense Recognized Related to Convertible Debt (Details) (Convertible Debt [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Convertible Senior Notes Due 2017
Schedule of Interest Expense Recognized Related to Convertible Debt [Line Items]
Contractual interest expense of convertible debt	$ 13,500	$ 13,500
Amortization of debt issuance costs	1,226	1,157
Amortization of debt discount	21,512	19,544
Total interest expense for convertible debt	36,238	34,201
Convertible Senior Notes Due 2019
Schedule of Interest Expense Recognized Related to Convertible Debt [Line Items]
Contractual interest expense of convertible debt	9,000	7,425
Amortization of debt issuance costs	1,282	1,025
Amortization of debt discount	11,829	9,223
Total interest expense for convertible debt	$ 22,111	$ 17,673