CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Class A Common Stock
Dividend declared common stock, per share (in dollars per share)	$ 0.264	$ 0.242	$ 0.792	$ 0.726
Class B Common Stock
Dividend declared common stock, per share (in dollars per share)	$ 0.240	$ 0.220	$ 0.720	$ 0.660