Earnings Per Common Share - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Sep. 30, 2014
Antidilutive securities excluded from computation of earnings per share
Remaining number of shares authorized to be repurchased (in shares)	10,100,000		50,000,000
Stock repurchased and retired during period (in shares)	2,800,000
Total consideration for repurchase of common stock	$ 92
Payments for repurchase of common stock	$ 87	$ 86
Dividends
Cash dividends per common share paid (in dollars per share)	$ 0.1	$ 0.095
Cash dividends per common share declared (in dollars per share)	$ 0.1	$ 0.095
Stock Options
Antidilutive securities excluded from computation of earnings per share
Antidilutive effect on computation of diluted earnings per common share (in shares)	221,000	1,000,000
Long-term stock awards
Antidilutive securities excluded from computation of earnings per share
Stock repurchased And retired during period to offset dilutive impact of awards granted shares (in shares)	800,000