Consolidated Statement of Shareholders' Equity (USD $) In Millions, except Share data, unless otherwise specified	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income	Deferred Equity Compensation
Beginning balance at Dec. 31, 2014	$ 5,758	$ 2	$ 1,887	$ 3,494	$ 370	$ 5
Beginning balance (in shares) at Dec. 31, 2014		158,306,661
Increase (Decrease) in Shareholders' Equity
Net Income	201			201
Dividends ($0.12 per share)	(19)			(19)
Common stock repurchases (in shares)		(5,860,291)
Common stock repurchases	(152)		(152)
Share-based compensation and other (in shares)		388,961
Share-based compensation and other	(2)		(2)
Other comprehensive income	0
Ending balance at Mar. 31, 2015	$ 5,786	$ 2	$ 1,733	$ 3,676	$ 370	$ 5
Ending balance (in shares) at Mar. 31, 2015		152,835,331