CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - shares	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	197,256	1,032,922
Common Stock Class A
Stock Issued During Period, Shares, New Issues	3,779,391
Common Stock Class D
Stock Repurchased During Period, Shares	509,347	3,911,860

Number of share options (or share units) exercised during the current period.

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Balance Type:	na
Period Type:	duration