QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Quarterly financial data
Total revenue	$ 184,385	$ 188,798	$ 185,293	$ 182,890	$ 182,943	$ 194,346	$ 193,753	$ 188,154	$ 741,366	$ 759,196	$ 619,145
Operating expenses	155,787	159,168	162,219	164,731	172,004	166,700	187,476	177,765	641,905	703,945	580,861
Income from operations	28,598	29,630	23,074	18,159	10,939	27,646	6,277	10,389	99,461	55,251	38,284
Other income (expense), net	37	(2,105)	(3,328)	(2,441)	(3,062)	(3,237)	(3,907)	(2,579)	(7,837)	(12,785)	18,905
INCOME BEFORE INCOME TAXES	28,635	27,525	19,746	15,718	7,877	24,409	2,370	7,810	91,624	42,466	57,189
Income taxes	14,184	9,513	7,979	6,781	4,494	11,193	1,052	3,830	38,457	20,569	19,607
NET INCOME	14,451	18,012	11,767	8,937	3,383	13,216	1,318	3,980	53,167	21,897	37,582
Net (income) loss attributable to non-controlling interests, net of tax	(1,335)	(2,047)	(1,237)	384	763	(1,880)	497	517	(4,235)	(103)	872
NET INCOME ATTRIBUTABLE TO ATLANTIC TELE-NETWORK, INC. STOCKHOLDERS	$ 13,116	$ 15,965	$ 10,530	$ 9,321	$ 4,146	$ 11,336	$ 1,815	$ 4,497	$ 48,932	$ 21,794	$ 38,454
Earnings per share (basic) (in dollars per share)	$ 0.84	$ 1.03	$ 0.68	$ 0.60	$ 0.27	$ 0.74	$ 0.12	$ 0.29	$ 3.15	$ 1.42	$ 2.51
Earnings per share (diluted) (in dollars per share)	$ 0.84	$ 1.02	$ 0.67	$ 0.60	$ 0.27	$ 0.73	$ 0.12	$ 0.29	$ 3.13	$ 1.41	$ 2.48