CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY
Cash dividends, common stock (in dollars per share)	$ 0.60	$ 0.54
Stock dividends, restricted stock units (in dollars per share)	$ 0.60	0.54
Stock dividends, accrued restricted stock awards (in dollars per share)		$ 0.54
Return of equity trust shares		28,648