Share-based Compensation Plans - Assumptions (Details) - Stock options - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assumptions used in the calculation of the weighted average fair value of options granted
Expected volatility (as a percent)	31.85%	36.27%	49.38%
Expected term	5 years	5 years	5 years 7 months 10 days
Dividend yield (as a percent)	3.30%	2.82%	0.67%
Risk free rate (as a percent)	1.31%	1.54%	1.75%
Weighted-average grant date fair value (in dollars per share)	$ 1.50	$ 1.97	$ 3.32