Valuation of debt and equity investments and certain liabilities (Tables)

9 Months Ended

Sep. 30, 2014

Fair Value Disclosures [Abstract]

Investments

Details of our investments are as follows:

	September 30, 2014						December 31, 2013
	Cash and Cash Equivalents		Short-term Investments		Long-term Investments		Cash and Cash Equivalents		Short-term Investments		Long-term Investments
Measured at fair value:
Available-for-sale securities
Money market funds	$	364	$	—	$	—	$	500	$	—	$	—
Corporate obligations	90		345		—		123		217		—
U.S. Government agency and Treasury securities	625		1,535		—		787		1,985		—
Trading securities
Mutual funds	—		—		180		—		—		179
Total	1,079		1,880		180		1,410		2,202		179
Other measurement basis:
Equity-method investments	—		—		27		—		—		24
Cost-method investments	—		—		12		—		—		13
Cash on hand	227		—		—		217		—		—
Total	$	1,306	$	1,880	$	219	$	1,627	$	2,202	$	216

Aggregate maturities of investments in debt securities classified as available for sale

The following table presents the aggregate maturities of investments in debt securities classified as available for sale at September 30, 2014:

Due	Fair Value
One year or less	$	2,759
One to two years	200

Assets and liabilities accounted for at fair value

The following are our assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2014, and December 31, 2013. For these periods, we had no Level 3 assets or liabilities. These tables do not include cash on hand, assets held by our postretirement plans, or assets and liabilities that are measured at historical cost or any basis other than fair value.

	Fair Value
	September 30, 2014		Level 1		Level 2
Assets:
Money market funds	$	364	$	364	$	—
Corporate obligations	435		—		435
U.S. Government agency and Treasury securities	2,160		1,595		565
Mutual funds	180		180		—
Total assets	$	3,139	$	2,139	$	1,000
Liabilities:
Deferred compensation	$	196	$	196	$	—
Total liabilities	$	196	$	196	$	—

	Fair Value
	December 31, 2013		Level 1		Level 2
Assets:
Money market funds	$	500	$	500	$	—
Corporate obligations	340		—		340
U.S. Government agency and Treasury securities	2,772		2,107		665
Mutual funds	179		179		—
Total assets	$	3,791	$	2,786	$	1,005
Liabilities:
Deferred compensation	$	197	$	197	$	—
Total liabilities	$	197	$	197	$	—