Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2013

Investments, Debt and Equity Securities [Abstract]

Summary of Marketable Securities

	2013							2012
	Cost		Unrealized Gains (Losses)			Fair Value		Cost		Unrealized Gains (Losses)		Fair Value
U.S. government securities	$	27	$	—		$	27	$	7	$	—	$	7
Corporate securities	30		(1		)	29		11				11
Certificates of deposit	21					21		16				16
Other	31		2			33		25		1		26
Total marketable securities	$	109	$	1		$	110	$	59	$	1	$	60