Common Stock Outstanding Roll Forward [Roll Forward]

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- Definition

Related Party Transaction, Common Stock, Shares Issued

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

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

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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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- Definition

Number of new stock issued during the period.

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- Definition

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

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

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Number of shares of common and preferred stock retired from treasury during the period.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Stock by Class (Details) - shares	12 Months Ended		19 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2017
Common Stock Outstanding Roll Forward [Roll Forward]
Retirement of Class A common shares in connection with the Company's stock repurchase plan (in shares)	(72,668,712)		(100,697,392)
Treasury Stock, Shares, Acquired	10,457,772	0
Ending balance common stock, shares outstanding (in shares)	632,995,139		632,995,139
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	2,157,000
Common Class A
Common Stock Outstanding Roll Forward [Roll Forward]
Beginning balance common stock, shares outstanding (in shares)	496,064,027	246,982,292
Altice Europe Distribution on June 8, 2018 (in shares)		242,402,231
Conversion of Class B common stock to Class A common stock (in shares)	26,730,427	34,708,184
Retirement of Class A common shares in connection with the Company's stock repurchase plan (in shares)		(28,028,680)
Stock Issued During Period, Shares, New Issues	6,897,190
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	184,147
Ending balance common stock, shares outstanding (in shares)	446,749,307	496,064,027	446,749,307
Common stock, shares issued (in shares)	496,064,027	496,064,027	496,064,027	246,982,292
Common Class B
Common Stock Outstanding Roll Forward [Roll Forward]
Beginning balance common stock, shares outstanding (in shares)	212,976,259	490,086,674
Altice Europe Distribution on June 8, 2018 (in shares)		(242,402,231)
Conversion of Class B common stock to Class A common stock (in shares)	(26,730,427)	(34,708,184)
Retirement of Class A common shares in connection with the Company's stock repurchase plan (in shares)		0
Stock Issued During Period, Shares, New Issues	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0
Ending balance common stock, shares outstanding (in shares)	186,245,832	212,976,259	186,245,832
Common stock, shares issued (in shares)		490,086,674		490,086,674