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Related Party Transaction, Other Expenses from Transactions with Related Party

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Transfer of Goodwill to an Affiliate in Connection With the Transfer of a Substantial Portion of the Company's Workforce

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- Definition

Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The amount for notes payable (written promise to pay), due to related parties.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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Amount of cash outflow to acquire investments classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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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No definition available.

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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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AFFILIATE AND RELATED PARTY TRANSACTIONS - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
	Jan. 08, 2018	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Jul. 06, 2016
Related Party Transaction [Line Items]
Investment in affiliates and related parties				$ 930	$ 5,606
Equity in net income (loss) from investment in related party				(10,040)	(1,132)
Prepayment to affiliate included in prepaid expenses and other current assets				130,425	102,219
Transfer of goodwill				(23,101)
Related party expense				640,344	132,427
Cash distributions to shareholders		$ 839,700		840,035	445,176
Cash distributions			$ 79,617	919,317	365,559
Affiliates
Related Party Transaction [Line Items]
Related party note					1,750,000
Due to related parties and affiliates					102,557
Fees for Executive Services \| Affiliates
Related Party Transaction [Line Items]
Related party expense				30,000	20,556
Related party transaction, annual fee				30,000
Equipment Purchase Costs \| Affiliates
Related Party Transaction [Line Items]
Capital expenditures					1,025
Equipment Purchase Costs \| Altice Labs S.A.
Related Party Transaction [Line Items]
Capital expenditures				17,434
Equipment Purchase Costs \| Altice Management International
Related Party Transaction [Line Items]
Capital expenditures					44,121
Software Development Service Costs \| Altice Labs S.A.
Related Party Transaction [Line Items]
Capital expenditures					740
Software Development Service Costs \| Altice Management International
Related Party Transaction [Line Items]
Capital expenditures				$ 4,578
Newsday
Related Party Transaction [Line Items]
Ownership percentage of noncontrolling interest						75.00%
Ownership percentage				25.00%
Equity in net income (loss) from investment in related party				$ 7,219	1,132
I24News and Altice NV 24/7
Related Party Transaction [Line Items]
Ownership percentage				25.00%
Equity in net income (loss) from investment in related party				$ 2,821	0
Newsday And i24News
Related Party Transaction [Line Items]
Investment in affiliates and related parties				(2,649)	5,606
CSC Holdings Revolving Credit Facility \| Revolving Credit Facility
Related Party Transaction [Line Items]
Cash distributions to shareholders				500,000
Proceeds from credit facility debt		$ 500,000		1,350,000
Other Operating Expense \| Transition Services \| Affiliates
Related Party Transaction [Line Items]
Other operating expenses, charges for related party services				4,057	887
Transition services credit				$ 917	$ 2,589
Subsequent Event
Related Party Transaction [Line Items]
Cash distributions to shareholders	$ 1,500,000