Stock Repurchase Plan and Dividend (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	0 Months Ended	3 Months Ended	9 Months Ended	0 Months Ended	3 Months Ended	9 Months Ended
	Jul. 23, 2014	Sep. 30, 2014	Sep. 30, 2014	Jul. 01, 2014 Common Stock [Member]	Sep. 30, 2014 Common Stock [Member]	Sep. 30, 2014 Common Stock [Member]	Jul. 23, 2014 Common Stock [Member] Dividend Declared [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 1,000,000,000
Stock repurchased (in shares)				0.4	2.9	2.9
Aggregate stock repurchase price				19,000,000	113,000,000	113,000,000
Average cost per share					$ 39.30	$ 39.30
Dividends payable, per share							$ 0.10
Total cash payment for dividends		$ 72,000,000	$ 72,000,000