Equity - Activity for Class B Common Stock and Treasury Stock (Details) - shares	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	8,375,077	8,702,074
Stock Award Activity	(649,581)	(498,324)
Purchase of Treasury Stock	714,251	60,833
Ending Balance	8,439,747	8,264,583
Class B Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	101,130,379	100,803,382
Stock Award Activity	649,581	498,324
Purchase of Treasury Stock	(714,251)	(60,833)
Ending Balance	101,065,709	101,240,873
Purchase of Treasury Stock	714,000

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The increase (decrease) during the period in the number of shares issued.

+ References

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

+ References

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- Definition

Number of treasury shares or units reissued. Excludes reissuance of shares or units in treasury for award under share-based payment arrangement.

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- Definition

Number of previously issued common shares repurchased by the issuing entity and held in treasury.

+ References

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Number of shares that have been repurchased during the period and are being held in treasury.

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