Debt and Capital Lease Obligations (Consolidated Debt and Capital Lease Obligations) (Schedules) (Details)	Dec. 31, 2016 EUR (€)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 GBP (£)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Estimated fair value		$ 344,400,000
Total debt before unamortized premiums, discounts and deferred financing costs		42,541,800,000		$ 45,781,200,000
Unamortized premiums (discounts), net		44,500,000		(46,700,000)
Unamortized deferred financing costs		(270,400,000)		(308,200,000)
Total carrying amount of debt		42,315,900,000		45,426,300,000
Total capital lease obligations		1,242,800,000		1,322,800,000
Total debt and capital lease obligations		43,558,700,000		46,749,100,000
Current maturities of debt and capital lease obligations		(2,775,100,000)		(2,537,900,000)
Long-term debt and capital lease obligations		40,783,600,000		44,211,200,000
Virgin Media [Member]
Debt Instrument [Line Items]
Limitation on availability to be borrowed, loaned or distributed		665,800,000	£ 539,300,000
Virgin Media [Member] | Pro Forma [Member]
Debt Instrument [Line Items]
Limitation on availability to be borrowed, loaned or distributed		833,300,000	£ 675,000,000.0
Unitymedia [Member]
Debt Instrument [Line Items]
Limitation on availability to be borrowed, loaned or distributed	€ 17,000,000.0	17,900,000
Unitymedia [Member] | Pro Forma [Member]
Debt Instrument [Line Items]
Limitation on availability to be borrowed, loaned or distributed	€ 211,500,000	$ 223,100,000
VM Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.60%	5.60%	5.60%
Unused borrowing capacity		$ 0	£ 0
Estimated fair value		9,311,000,000.0		10,594,100,000
Total debt before unamortized premiums, discounts and deferred financing costs		$ 9,041,000,000.0		10,551,500,000
VM Credit Facility [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.69%	3.69%	3.69%
Estimated fair value		$ 4,531,500,000		3,413,700,000
Total debt before unamortized premiums, discounts and deferred financing costs		$ 4,505,500,000		3,471,100,000
Unitymedia Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.01%	5.01%	5.01%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		7,679,700,000		7,631,600,000
Total debt before unamortized premiums, discounts and deferred financing costs		7,419,300,000		7,682,000,000.0
Total carrying amount of debt		$ 7,368,900,000
Unitymedia Revolving Credit Facilities [Member]
Debt Instrument [Line Items]
Weighted average interest rate	0.00%	0.00%	0.00%
Unused borrowing capacity		$ 527,400,000
Unused borrowing capacity	€ 500,000,000.0	527,400,000
Estimated fair value		0		0
Total debt before unamortized premiums, discounts and deferred financing costs		0		0
Limitation on availability to be borrowed, loaned or distributed	434,500,000	458,300,000
Unitymedia Revolving Credit Facilities [Member] | Pro Forma [Member]
Debt Instrument [Line Items]
Limitation on availability to be borrowed, loaned or distributed	€ 500,000,000.0	$ 527,400,000
UPCB SPE Notes Debt [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.88%	4.88%	4.88%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		1,783,700,000		3,131,700,000
Total debt before unamortized premiums, discounts and deferred financing costs		$ 1,772,800,000		3,142,000,000.0
UPC Holding Senior Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	6.59%	6.59%	6.59%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		1,569,800,000		1,601,400,000
Total debt before unamortized premiums, discounts and deferred financing costs		1,451,500,000		1,491,100,000
Total carrying amount of debt		$ 1,441,000,000.0
UPC Broadband Holding Bank Facility [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.83%	3.83%	3.83%
Unused borrowing capacity		$ 1,044,300,000
Unused borrowing capacity	€ 990,100,000	1,044,300,000
Estimated fair value		2,811,900,000		1,284,300,000
Total debt before unamortized premiums, discounts and deferred financing costs		2,782,800,000		1,305,000,000.0
Limitation on availability to be borrowed, loaned or distributed	676,000,000.0	713,000,000.0
UPC Broadband Holding Bank Facility [Member] | Pro Forma [Member]
Debt Instrument [Line Items]
Limitation on availability to be borrowed, loaned or distributed	€ 990,100,000	$ 1,044,300,000
Telenet Credit Facility [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.46%	3.46%	3.46%
Unused borrowing capacity		$ 574,900,000
Unused borrowing capacity	€ 545,000,000.0	574,900,000
Estimated fair value		3,210,000,000.0		1,443,000,000.0
Total debt before unamortized premiums, discounts and deferred financing costs		$ 3,187,500,000		1,474,500,000
Telenet SPE Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.76%	5.76%	5.76%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		1,383,900,000		2,155,800,000
Total debt before unamortized premiums, discounts and deferred financing costs		1,297,300,000		2,097,200,000
Total carrying amount of debt		$ 1,282,000,000.0
ITV Collar Loan [Member]
Debt Instrument [Line Items]
Weighted average interest rate	1.35%	1.35%	1.35%
Unused borrowing capacity		$ 0
Estimated fair value		1,323,700,000		1,547,900,000
Total debt before unamortized premiums, discounts and deferred financing costs		$ 1,336,200,000		1,594,700,000
Sumitomo Collar Loan [Member]
Debt Instrument [Line Items]
Weighted average interest rate	1.88%	1.88%	1.88%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		499,700,000		805,600,000
Total debt before unamortized premiums, discounts and deferred financing costs		$ 488,200,000		787,600,000
Derivative Related Debt Instruments [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.43%	3.43%	3.43%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		450,700,000		0
Total debt before unamortized premiums, discounts and deferred financing costs		$ 426,300,000		0
Ziggo Group Holding [Member]
Debt Instrument [Line Items]
Weighted average interest rate	0.00%	0.00%	0.00%
Estimated fair value				7,698,800,000
Total debt before unamortized premiums, discounts and deferred financing costs				7,861,300,000
Other Debt [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.85%	3.85%	3.85%
Unused borrowing capacity		$ 0
Estimated fair value		558,700,000		395,000,000.0
Total debt before unamortized premiums, discounts and deferred financing costs		$ 564,500,000		291,800,000
CWC Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	7.31%	7.31%	7.31%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		2,319,600,000		0
Total debt before unamortized premiums, discounts and deferred financing costs		$ 2,181,100,000		0
CWC Credit Facilities [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.11%	5.11%	5.11%
Unused borrowing capacity		$ 756,500,000
Estimated fair value		1,427,900,000		0
Total debt before unamortized premiums, discounts and deferred financing costs		1,411,900,000		0
Limitation on availability to be borrowed, loaned or distributed		612,500,000
CWC Credit Facilities [Member] | Pro Forma [Member]
Debt Instrument [Line Items]
Limitation on availability to be borrowed, loaned or distributed		$ 612,500,000
VTR Senior Secured Notes [Member]
Debt Instrument [Line Items]
Weighted average interest rate	6.88%	6.88%	6.88%
Unused borrowing capacity	€ 0	$ 0
Estimated fair value		1,463,900,000		1,301,100,000
Total debt before unamortized premiums, discounts and deferred financing costs		$ 1,400,000,000.0		1,400,000,000.0
VTR Credit Facility [Member]
Debt Instrument [Line Items]
Weighted average interest rate	0.00%	0.00%	0.00%
Unused borrowing capacity		$ 192,800,000
Estimated fair value		0		0
Total debt before unamortized premiums, discounts and deferred financing costs		$ 0		0
Liberty Puerto Rico Bank Facility [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.11%	5.11%	5.11%
Unused borrowing capacity		$ 40,000,000.0
Unused borrowing capacity		40,000,000.0
Estimated fair value		935,200,000		913,000,000.0
Total debt before unamortized premiums, discounts and deferred financing costs		$ 942,500,000		942,500,000
Third-Party Debt [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.81%	4.81%	4.81%
Unused borrowing capacity		$ 3,969,200,000
Estimated fair value		$ 43,594,300,000		45,605,900,000
Liberty Global Group [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.56%	4.56%	4.56%
Unused borrowing capacity		$ 2,979,900,000
Estimated fair value		37,398,800,000		43,391,800,000
Total debt before unamortized premiums, discounts and deferred financing costs		36,557,400,000		43,438,700,000
Unamortized premiums (discounts), net		(39,600,000)
Unamortized deferred financing costs		(228,100,000)
Total capital lease obligations		1,221,100,000		1,321,900,000
Liberty Global Group [Member] | Telenet [Member]
Debt Instrument [Line Items]
Unamortized premiums (discounts), net		0
Unamortized deferred financing costs		(38,500,000)
Total capital lease obligations		374,000,000.0		371,100,000
Liberty Global Group [Member] | Virgin Media [Member]
Debt Instrument [Line Items]
Unamortized premiums (discounts), net		13,900,000
Unamortized deferred financing costs		(106,300,000)
Total capital lease obligations		91,200,000		159,500,000
Liberty Global Group [Member] | Other Subsidiaries [Member]
Debt Instrument [Line Items]
Unamortized premiums (discounts), net		(38,900,000)
Unamortized deferred financing costs		(1,200,000)
Total capital lease obligations		98,900,000		88,200,000
Liberty Global Group [Member] | Unitymedia [Member]
Debt Instrument [Line Items]
Unamortized premiums (discounts), net		0
Unamortized deferred financing costs		(50,300,000)
Total capital lease obligations		$ 657,000,000.0		703,100,000
Liberty Global Group [Member] | Vendor Financing [Member]
Debt Instrument [Line Items]
Weighted average interest rate	3.78%	3.78%	3.78%
Unused borrowing capacity		$ 0
Estimated fair value		2,284,500,000		1,688,900,000
Total debt before unamortized premiums, discounts and deferred financing costs		$ 2,284,500,000		1,688,900,000
LiLAC Group [Member]
Debt Instrument [Line Items]
Weighted average interest rate	6.33%	6.33%	6.33%
Unused borrowing capacity		$ 989,300,000
Estimated fair value		6,195,500,000		2,214,100,000
Total debt before unamortized premiums, discounts and deferred financing costs		5,984,400,000		2,342,500,000
Unamortized premiums (discounts), net		84,100,000
Unamortized deferred financing costs		(42,300,000)
Total capital lease obligations		21,700,000		900,000
LiLAC Group [Member] | CWC [Member]
Debt Instrument [Line Items]
Unamortized premiums (discounts), net		91,600,000
Unamortized deferred financing costs		(9,800,000)
Total capital lease obligations		20,800,000		0
LiLAC Group [Member] | Liberty Puerto Rico [Member]
Debt Instrument [Line Items]
Unamortized premiums (discounts), net		(7,500,000)
Unamortized deferred financing costs		(7,800,000)
Total capital lease obligations		700,000		300,000
LiLAC Group [Member] | VTR [Member]
Debt Instrument [Line Items]
Unamortized premiums (discounts), net		0
Unamortized deferred financing costs		(24,700,000)
Total capital lease obligations		$ 200,000		600,000
LiLAC Group [Member] | Vendor Financing [Member]
Debt Instrument [Line Items]
Weighted average interest rate	5.50%	5.50%	5.50%
Unused borrowing capacity		$ 0
Estimated fair value		48,900,000		0
Total debt before unamortized premiums, discounts and deferred financing costs		$ 48,900,000		$ 0