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Consolidation, Wholly Owned Subsidiary, Parent Ownership Interest, Percent

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Controlling Interest, Voting Power of Parent Company, Percentage

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Amount of decrease in additional paid in capital (APIC) resulting from dividends legally declared (or paid) in excess of retained earnings balance.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Amount of decrease of par value, additional paid in capital (APIC) and retained earnings of common and preferred stock retired from treasury when treasury stock is accounted for under the cost method.

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

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DESCRIPTION OF BUSINESS AND RELATED MATTERS (Details)			1 Months Ended	3 Months Ended				9 Months Ended		16 Months Ended
DESCRIPTION OF BUSINESS AND RELATED MATTERS (Details)	Jun. 06, 2018 USD ($)	May 22, 2018 $ / shares	Jan. 31, 2018 USD ($)	Sep. 30, 2019 USD ($) $ / shares shares	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2018 USD ($) $ / shares	Sep. 30, 2019 USD ($) segment $ / shares shares	Sep. 30, 2018 USD ($) $ / shares	Sep. 30, 2019 USD ($) shares	Jul. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 08, 2018
Business Acquisition [Line Items]
Number of segments \| segment								1
Goodwill				$ 8,138,511,000				$ 8,138,511,000		$ 8,138,511,000		$ 8,012,416,000
Cash dividends declared per common share (in dollars per share) \| $ / shares		$ 2.035		$ 0			$ 0	$ 0	$ 0
Dividend paid	$ 1,499,935,000
Stock Repurchase Program, Number of Shares Authorized to be Repurchased							$ 2,000,000,000.0		$ 2,000,000,000.0
Number of shares repurchased (in shares) \| shares								72,668,712
Value of shares repurchased								$ 1,686,873,000
Shares repurchased (in shares) \| shares										100,697,392
Value of shares repurchased				$ 486,920,000	$ 599,952,000	$ 600,001,000	240,799,000			$ 2,186,874,000
Availability remaining under its stock repurchase program				$ 4,813,126,000				$ 4,813,126,000		$ 4,813,126,000
Common stock, shares outstanding (in shares) \| shares				636,827,486				636,827,486		636,827,486
Altice Technical Services
Business Acquisition [Line Items]
Percentage of shares acquired			70.00%
Consideration transfered			$ 1.00
Interest owned								100.00%
Goodwill			$ 23,101,000
Altice N.V. Distribution \| Altice N.V.
Business Acquisition [Line Items]
Controlling interest percent													67.20%
Common stock conversion ratio													0.4163
Retained Earnings
Business Acquisition [Line Items]
Decrease in connection with dividends paid	536,224,000
Additional Paid-in Capital
Business Acquisition [Line Items]
Decrease in connection with dividends paid	$ 963,711,000
Value of shares repurchased				$ 486,736,000	$ 599,703,000	$ 599,707,000	$ 240,666,000
2019 Share Repurchase Authorization [Member]
Business Acquisition [Line Items]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased											$ 5,000,000,000.0