Investments in Unconsolidated Affiliates - Equity Method Investment Summarized Financial Information, Balance Sheet (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Equity Method Investments and Joint Ventures [Abstract]
Current assets	$ 182	$ 207
Long-term assets	5,200	5,157
Current liabilities	(170)	(200)
Long-term liabilities	(216)	(164)
Net assets	$ 4,996	$ 5,000

The amount of assets reported by an equity method investment of the entity.

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