CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) (Parenthetical) - $ / shares	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Stockholders Equity [Abstract]
Cash dividends paid per share	$ 0.02	$ 0.02	$ 0.02	$ 0.02	$ 0.04	$ 0.04