(5) Investment in Sunrise Energy (Detail) - Condensed Statement of Operations (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Revenue	$ 37,662	$ 33,956
Expenses	(30,741)	(24,784)
Net income	5,468	6,153
Sunrise Energy
Revenue	812	607
Expenses	(568)	(495)
Net income	$ 244	$ 112

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 10: http://www.xbrl.org/2003/role/presentationRef

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Reference 11: http://www.xbrl.org/2003/role/presentationRef

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Reference 16: http://www.xbrl.org/2003/role/presentationRef

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+ Details