(4) Investment in Sunrise Energy (Detail) - Condensed Balance Sheet (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets	$ 50,914	$ 48,876
	234,644	232,428
Total liabilities	63,950	71,435
	234,644	232,428
Sunrise Energy
Current assets	2,368
Oil and gas properties, net	6,211
	8,579
Total liabilities	922
Partners' capital	7,657
	$ 8,579

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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