v3.10.0.1

Earnings or Loss per Share (Schedules) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings (loss) from continuing operations	$ 668.7	$ (761.3)	$ (696.3)	$ (1,126.8)
Net earnings from continuing operations attributable to noncontrolling interests	(36.1)	(4.8)	(42.2)	(39.8)
Net earnings (loss) from continuing operations attributable to Liberty Global shareholders	$ 632.6	$ (766.1)	$ (738.5)	$ (1,166.6)
Weighted average ordinary shares outstanding (Liberty Global Shares):
Basic (in shares)	788,815,021	853,612,217	798,215,803	871,936,668
Incremental shares attributable to the assumed exercise of outstanding options, SARs [and PSARs] and the release of [restricted shares and] share units upon vesting (treasury stock method) (in shares)	3,105,000
Diluted (in shares)	791,920,021	853,612,217	798,215,803	871,936,668

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