CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - shares	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		15,000
Common Stock Class A
Stock Repurchased During Period, Shares		54,896
Stock Issued During Period, Shares, New Issues	2,859,276
Class D common stock
Stock Repurchased During Period, Shares	3,915,055	2,588,796
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	1,032,922
Stock Issued During Period, Shares, New Issues		755,239