CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total ATNI Stockholders' Equity	Common Stock	Treasury Stock, at cost	Additional Paid In Capital	Retained Earnings	Accumulated Other Comprehensive Income/(Loss)	Non-Controlling Interests	Total
Balance, beginning of period at Dec. 31, 2018	$ 695,387	$ 172	$ (48,547)	$ 181,778	$ 563,593	$ (1,609)	$ 127,937	$ 823,324
Increase (Decrease) in Stockholders' Equity
Purchase of shares of common stock	(1,578)		(1,578)					(1,578)
Stock-based compensation	3,334			3,334				3,334
Dividends declared on common stock	(5,352)				(5,352)		(3,904)	(9,256)
Repurchase of non-controlling interests							(861)	(861)
Investments made by minority shareholders in consolidated affiliates							488	488
Comprehensive income:
Net income (loss)	(2,435)				(2,435)		5,198	2,763
Other comprehensive income	327					327		327
Comprehensive income	(2,108)						5,198	3,090
Balance, end of period at Jun. 30, 2019	689,683	172	(50,125)	185,112	555,806	(1,282)	128,858	818,541
Balance, beginning of period at Mar. 31, 2019	691,021	172	(50,116)	183,079	559,319	(1,433)	128,963	819,984
Increase (Decrease) in Stockholders' Equity
Purchase of shares of common stock	(9)		(9)					(9)
Stock-based compensation	2,033			2,033				2,033
Dividends declared on common stock	(2,657)				(2,657)		(2,348)	(5,005)
Repurchase of non-controlling interests							(640)	(640)
Comprehensive income:
Net income (loss)	(856)				(856)		2,883	2,027
Other comprehensive income	151					151		151
Comprehensive income	(705)						2,883	2,178
Balance, end of period at Jun. 30, 2019	689,683	172	(50,125)	185,112	555,806	(1,282)	128,858	818,541
Balance, beginning of period at Dec. 31, 2019	676,122	172	(51,129)	188,471	541,890	(3,282)	129,961	806,083
Increase (Decrease) in Stockholders' Equity
Purchase of shares of common stock	(4,187)		(4,187)					(4,187)
Stock-based compensation	2,614			2,614			107	2,721
Dividends declared on common stock	(5,440)				(5,440)		(5,553)	(10,993)
Repurchase of non-controlling interests	(1,300)			(1,300)			(2,611)	(3,911)
Comprehensive income:
Net income (loss)	3,733				3,733		7,009	10,742
Other comprehensive income	(2,812)					(2,812)		(2,812)
Comprehensive income	921						7,009	7,930
Balance, end of period at Jun. 30, 2020	668,730	172	(55,316)	189,785	540,183	(6,094)	128,913	797,643
Balance, beginning of period at Mar. 31, 2020	665,758	172	(54,358)	189,667	538,161	(7,884)	127,321	793,079
Increase (Decrease) in Stockholders' Equity
Purchase of shares of common stock	(958)		(958)					(958)
Stock-based compensation	1,418			1,418			131	1,549
Dividends declared on common stock	(2,724)				(2,724)		(1,321)	(4,045)
Repurchase of non-controlling interests	(1,300)			(1,300)			(836)	(2,136)
Comprehensive income:
Net income (loss)	4,746				4,746		3,618	8,364
Other comprehensive income	1,790					1,790		1,790
Comprehensive income	6,536						3,618	10,154
Balance, end of period at Jun. 30, 2020	$ 668,730	$ 172	$ (55,316)	$ 189,785	$ 540,183	$ (6,094)	$ 128,913	$ 797,643