Amount of cash distribution paid to unit-holder of limited partnership (LP).

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Per unit of ownership amount of cash distributions paid to unit-holder of a limited partnership (LP).

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

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Aggregate amount of cumulative preferred dividends in arrears.

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Cash Distribution and Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands										9 Months Ended	12 Months Ended
	Sep. 18, 2019	Aug. 07, 2019	May 15, 2019	May 08, 2019	Feb. 21, 2019	Nov. 21, 2018	Aug. 22, 2018	May 23, 2018	Feb. 20, 2018	Sep. 30, 2019	Dec. 31, 2018
Partnership equity and distributions
Cash dividends declared per common share										$ 0.3075
Antero Midstream GP LP \| Common shareholders
Partnership equity and distributions
Distributions	$ 138	$ 154,146	$ 98	$ 152,082	$ 30,543	$ 26,817	$ 23,276	$ 20,109	$ 13,964	$ 337,007	$ 84,166
Distributions per share (in dollars per share)		$ 0.3075		$ 0.3025	$ 0.164	$ 0.144	$ 0.125	$ 0.108	$ 0.075
Series A Preferred Stock
Partnership equity and distributions
Cash dividend declared										138
Dividends in arrears										$ 69