Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919359-209981

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Change in adjusted earnings from continuing operations before interest income taxes, depreciation and amortization.

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- Definition

Number of dark fiber leased.

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SEGMENT REPORTING (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
SEGMENT REPORTING (Narrative) (Details) $ in Millions	Jun. 30, 2019 segment	Mar. 31, 2019 USD ($)	Mar. 31, 2019 USD ($) item segment
Segment Reporting Information [Line Items]
Number of segments \| segment	4		6
Fiber Solutions [Member] \| Minimum
Segment Reporting Information [Line Items]
Number of dark fiber pairs leased to customers \| item			2
Contract term		3 years	3 years
Fiber Solutions [Member] \| Maximum
Segment Reporting Information [Line Items]
Number of dark fiber pairs leased to customers \| item			12
Contract term		20 years	20 years
Transport [Member] \| Minimum
Segment Reporting Information [Line Items]
Contract term		2 years	2 years
Transport [Member] \| Maximum
Segment Reporting Information [Line Items]
Contract term		5 years	5 years
Enterprise Networks [Member]
Segment Reporting Information [Line Items]
Increase (decrease) in segment adjusted EBITDA \| $		$ 0.7	$ 2.1
Enterprise Networks [Member] \| Minimum
Segment Reporting Information [Line Items]
Contract term		1 year	1 year
Enterprise Networks [Member] \| Maximum
Segment Reporting Information [Line Items]
Contract term		10 years	10 years
zColo [Member] \| Minimum
Segment Reporting Information [Line Items]
Contract term		2 years	2 years
zColo [Member] \| Maximum
Segment Reporting Information [Line Items]
Contract term		5 years	5 years
Other [Member]
Segment Reporting Information [Line Items]
Contract term		1 year	1 year
Allstream [Member]
Segment Reporting Information [Line Items]
Increase (decrease) in segment adjusted EBITDA \| $		$ (0.7)	$ (2.1)