Note 1 - Summary of Significant Accounting Policies - Summary of Reconciliation of Cash, Cash Equivalents, and Restricted Cash in the Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash, cash equivalents and restricted cash, beginning of period	$ 278,629	$ 233,711	$ 189,326
Cash and cash equivalents	262,273	272,804	233,711
Restricted cash	5,835	5,825	0
Total cash, cash equivalents and restricted cash, end of period	268,108	278,629	233,711
Net (decrease) increase in cash, cash equivalents and restricted cash	$ (10,521)	$ 44,918	$ 44,385