Investments (Investee Summarized Balance Sheet Information) (Details) (Clearwire [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Clearwire [Member]
Current assets	$ 988	$ 1,287
Noncurrent assets	6,678	7,556
Current liabilities	405	280
Noncurrent liabilities	$ 5,379	$ 4,917

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

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+ Details

- Definition

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

+ References

+ Details

- Definition

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

+ References

+ Details

- Definition

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

+ References

+ Details