CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Stockholders Equity [Abstract]
Cash dividends declared per common share (in dollars per share)	$ 0.28	$ 0.27	$ 0.84	$ 0.81