v3.10.0.1

Summary of Significant Accounting Policies (Details 1) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Accounting change (note 2)		$ 324.5	$ 15.3
Aggregate allowance for doubtful accounts	$ 45.8	74.2
Increase to allowance for doubtful accounts	86.1
Asset retirement obligation	53.5	58.3
Earnings (loss) from continuing operations	(1,411.5)	(2,350.0)	1,650.3
Net earnings from continuing operations attributable to noncontrolling interests	(120.5)	(71.4)	(25.8)
Net earnings (loss) from continuing operations attributable to Liberty Global shareholders	$ (1,532.0)	$ (2,421.4)	$ 1,624.5
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Basic (in shares)	778,675,957	847,894,601	889,790,968
Diluted (in shares)	778,675,957	847,894,601	899,969,654
Numerator:
Net earnings attributable to holders of Liberty Global Shares (basic EPS computation)	$ (1,532.0)	$ (2,421.4)	$ 1,624.5
Interest expense on Virgin Media’s 6.50% convertible senior notes			1.7
Net earnings attributable to holders of Liberty Global Shares (diluted EPS computation)			$ 1,626.2
Denominator:
Weighted average ordinary shares (basic EPS computation) (in shares)	778,675,957	847,894,601	889,790,968
Incremental shares attributable to the assumed exercise and vesting of share incentive awards (treasury stock method) (in shares)			7,819,514
Incremental shares attributable to the assumed conversion of Virgin Media’s 6.5% convertible senior notes (in shares)			2,359,172
Weighted average ordinary shares (diluted EPS computation) (in shares)	778,675,957	847,894,601	899,969,654

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