Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Property, plant and equipment, net (related to VIEs)	$ 1,535,757us-gaap_PropertyPlantAndEquipmentNet	$ 1,437,637us-gaap_PropertyPlantAndEquipmentNet
Construction-in-process (related to VIEs)	230,037us-gaap_ConstructionInProgressGross	296,722us-gaap_ConstructionInProgressGross
Senior unsecured bonds %	7.00%	7.00%
Senior unsecured bonds unamortized premium	744	744
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000us-gaap_CommonStockSharesAuthorized	200,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	48,828,331us-gaap_CommonStockSharesIssued	45,537,162us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	48,828,331us-gaap_CommonStockSharesOutstanding	45,537,162us-gaap_CommonStockSharesOutstanding
Variable Interest Entity, Primary Beneficiary [Member]
Property, plant and equipment, net (related to VIEs)	1,421,996	1,339,342
Construction-in-process (related to VIEs)	$ 82,045	$ 162,006

Face amount or stated value per share of common stock.

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