CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Accounts receivable, allowances	$ 3	$ 3
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10	10
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	600	600
Common stock, shares issued	382	525
Common stock, shares outstanding	365	382
Treasury stock, shares	17	143