Dividends - Cash Dividends per Common Share (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Equity [Abstract]
Cash dividends per common share (in dollars per share)	$ 0.19	$ 0.18	$ 0.55	$ 0.53