v3.10.0.1

Segment Reporting (Narrative) (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Jun. 30, 2018 | Dec. 31, 2016
Segment Reporting Information [Line Items] |  |  |
Threshold percentage used to determine reportable segments using one of three criteria of revenue, operating cash flow or total assets | 10.00% |  |
Performance measures, percentage of reportable segment revenue and operating cash flow presented | 100.00% |  |
VodafoneZiggo JV |  |  |
Segment Reporting Information [Line Items] |  |  |
Percentage of minority interest revenues and expenses included in net earnings attributable to noncontrolling interest | 100.00% |  |
Ownership percentage | 50.00% | 50.00% | 50.00%
Telenet |  |  |
Segment Reporting Information [Line Items] |  |  |
Percentage of minority interest revenues and expenses included in net earnings attributable to noncontrolling interest | 100.00% |  |

X
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