CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares				12 Months Ended
	Feb. 08, 2018	Feb. 09, 2017	Feb. 11, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Stockholders' Equity [Abstract]
Dividends per common share (in dollars per share)	$ 0.34	$ 0.30	$ 0.26	$ 0.34	$ 0.30	$ 0.26