(5) Investment in Sunrise Energy (Detail) - Condensed Balance Sheet (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets	$ 34,106	$ 34,863
	234,628	229,207
Total liabilities	66,377	67,198
	234,628	229,207
Sunrise Energy
Current assets	2,041
Oil and gas properties, net	6,858
	8,899
Total liabilities	728
Partners' capital	8,171
	$ 8,899

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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The amount of ownership interest of different classes of partners in limited partnership.

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