Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, plant and equipment, net (related to VIEs)	$ 1,437,637us-gaap_PropertyPlantAndEquipmentNet	$ 1,452,336us-gaap_PropertyPlantAndEquipmentNet
Construction-in-process (related to VIEs)	296,722us-gaap_ConstructionInProgressGross	288,827us-gaap_ConstructionInProgressGross
Senior unsecured bonds %	7.00%	7.00%
Senior unsecured bonds unamortized premium	820	820
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	45,537,162us-gaap_CommonStockSharesIssued	45,460,653us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	45,537,162us-gaap_CommonStockSharesOutstanding	45,460,653us-gaap_CommonStockSharesOutstanding
Variable Interest Entity, Primary Beneficiary [Member]
Property, plant and equipment, net (related to VIEs)	1,339,342	1,381,083
Construction-in-process (related to VIEs)	$ 162,006	$ 136,947

Face amount or stated value per share of common stock.

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