Note 2 - Summary of Significant Accounting Policies - Effect of the Accounting Change on the Statements of Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Net cash provided by operating activities	$ 40,305	$ 46,428
Net cash used in investing activities	8,775	(36,902)
Net (Decrease) Increase in Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	35,007	4,929
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Beginning of Period	31,589	49,314
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, End of Period	$ 66,596	54,243
New Accounting Pronouncement, Early Adoption, Effect [Member]
Restricted cash and cash equivalents
Net cash provided by operating activities		46,428
Change in restricted cash and cash equivalents
Net cash used in investing activities		(36,902)
Net (Decrease) Increase in Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents		4,929
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Beginning of Period		49,314
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, End of Period		54,243
New Accounting Pronouncement, Early Adoption, Effect [Member] \| Scenario, Previously Reported [Member]
Restricted cash and cash equivalents		(10,342)
Net cash provided by operating activities		36,086
Change in restricted cash and cash equivalents		4,748
Net cash used in investing activities		(32,154)
Net (Decrease) Increase in Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents		(665)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Beginning of Period		38,208
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, End of Period		37,543
New Accounting Pronouncement, Early Adoption, Effect [Member] \| Restatement Adjustment [Member]
Restricted cash and cash equivalents		10,342
Net cash provided by operating activities		10,342
Change in restricted cash and cash equivalents		(4,748)
Net cash used in investing activities		(4,748)
Net (Decrease) Increase in Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents		5,594
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Beginning of Period		11,106
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, End of Period		$ 16,700

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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