(4) Investment in Sunrise Energy (Detail) - Condensed Balance Sheet (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current assets	$ 43,604	$ 48,876
	228,608	232,428
Total liabilities	65,307	71,435
	228,608	232,428
Sunrise Energy
Current assets	2,390
Oil and gas properties, net	6,731
	9,121
Total liabilities	1,430
Members' capital	7,691
	$ 9,121

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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