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GOODWILL AND INTANGIBLE ASSETS - Change In Carrying Amount Of Telecommunications Licenses (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Changes in the carrying amount of the company's telecommunications licenses, by operating segment |  |  |  |
Balance at the beginning of the period |  | $ 95,952 |  |
Balance at the end of the period |  | 93,686 | $ 95,952 |
Telecommunications Licenses |  |  |  |
Telecommunications licenses |  |  |  |
Discounted rate used for cash flows (as a percent) | 14.50% |  |  |
Impairment of intangible assets | $ 0 | 0 | 0 | $ 0
Changes in the carrying amount of the company's telecommunications licenses, by operating segment |  |  |  |
Balance at the beginning of the period |  | 95,952 | 48,291 |
Acquired licenses |  | 485 | 47,692 |
Dispositions |  | (2,750) | (31) |
Balance at the end of the period |  | 93,687 | 95,952 | 48,291
Telecommunications Licenses | U.S. Telecom |  |  |  |
Changes in the carrying amount of the company's telecommunications licenses, by operating segment |  |  |  |
Balance at the beginning of the period |  | 72,605 | 24,944 |
Acquired licenses |  | 485 | 47,692 |
Dispositions |  | (2,750) | (31) |
Balance at the end of the period |  | 70,340 | 72,605 | 24,944
Telecommunications Licenses | International Telecom |  |  |  |
Changes in the carrying amount of the company's telecommunications licenses, by operating segment |  |  |  |
Balance at the beginning of the period |  | 23,347 | 23,347 |
Balance at the end of the period |  | $ 23,347 | $ 23,347 | $ 23,347

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- Definition Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the capitalized costs to acquire rights under a license arrangement (for example, to sell specified products in a specified territory) having an indefinite period of benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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