Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property, plant and equipment, net	$ 1,835,939	$ 1,734,691
Construction-in-process	$ 351,288	$ 293,542
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	50,672,520	50,609,051
Common stock, shares outstanding (in shares)	50,672,520	50,609,051
Senior Secured Notes [Member]
Deferred financing costs	$ 7,758	$ 8,113
Other Loans, Limited and Non-recourse [Member]
Deferred financing costs	4,823	5,258
Senior Unsecured Bonds [Member]
Deferred financing costs	804	580
Other Loans, Full Recourse [Member]
Deferred financing costs	1,058	1,011
Variable Interest Entity, Primary Beneficiary [Member]
Property, plant and equipment, net	1,744,299	1,631,900
Construction-in-process	$ 106,977	$ 142,717

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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