v3.19.3

Preferred Members' Interest - Additional Information (Detail) - Mediacom LLC [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jul. 31, 2001
Class Of Stock [Line Items]
Preferred equity investment					$ 150.0
Percentage of annual cash dividend on preferred equity investment			12.00%
Cash dividends on PMI	$ 4.5	$ 4.5	$ 13.5	$ 13.5

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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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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Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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The percentage rate used to calculate dividend payments on preferred stock.

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MEDIACOM BROADBAND LLC 10-Q