Debt and Capital Lease Obligations (VM Notes) (Details) € in Millions, £ in Millions			12 Months Ended
	Apr. 30, 2015 USD ($)	Apr. 30, 2015 GBP (£)	Dec. 31, 2016 EUR (€)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 GBP (£)
Debt Instrument [Line Items]
Stated interest rate of debt			4.875%			4.875%	4.875%
Outstanding principal amount				$ 45,781,200,000		$ 42,541,800,000
Estimated fair value						344,400,000
Carrying value				45,426,300,000		42,315,900,000
VM Notes [Member]
Debt Instrument [Line Items]
Outstanding principal amount				10,551,500,000		9,041,000,000.0
Estimated fair value				10,594,100,000		$ 9,311,000,000.0
Additional basis points used to determine redemption premium			50.00%			50.00%	50.00%
VM Senior Notes [Member]
Debt Instrument [Line Items]
Outstanding principal amount						$ 9,041,000,000.0
Estimated fair value						9,311,000,000.0
Carrying value						$ 9,009,400,000
2022 VM 4.875% Dollar Senior Notes
Debt Instrument [Line Items]
Stated interest rate of debt			4.875%			4.875%	4.875%
Original issue amount						$ 118,700,000
Outstanding principal amount						118,700,000
Estimated fair value						105,800,000
Carrying value						$ 119,300,000
2022 VM 5.25% Dollar Senior Notes
Debt Instrument [Line Items]
Stated interest rate of debt			5.25%			5.25%	5.25%
Original issue amount						$ 95,000,000.0
Outstanding principal amount						95,000,000.0
Estimated fair value						85,000,000.0
Carrying value						$ 95,500,000
2022 VM Sterling Senior Notes
Debt Instrument [Line Items]
Stated interest rate of debt			5.125%			5.125%	5.125%
Original issue amount | £							£ 44.1
Outstanding principal amount						$ 54,400,000	£ 44.1
Estimated fair value						55,300,000
Carrying value						$ 54,800,000
2023 VM Dollar Senior Notes
Debt Instrument [Line Items]
Stated interest rate of debt			6.375%			6.375%	6.375%
Original issue amount						$ 530,000,000.0
Outstanding principal amount						530,000,000.0
Estimated fair value						551,900,000
Carrying value						$ 523,100,000
2023 VM Dollar Senior Notes | 2018
Debt Instrument [Line Items]
Redemption price			103.188%
2023 VM Dollar Senior Notes | 2019
Debt Instrument [Line Items]
Redemption price			102.125%
2023 VM Dollar Senior Notes | 2020
Debt Instrument [Line Items]
Redemption price			101.063%
2023 VM Dollar Senior Notes | 2021
Debt Instrument [Line Items]
Redemption price			100.00%
2023 VM Dollar Senior Notes | 2022
Debt Instrument [Line Items]
Redemption price			100.00%
2023 VM Sterling Senior Notes
Debt Instrument [Line Items]
Stated interest rate of debt			7.00%			7.00%	7.00%
Original issue amount | £							£ 250.0
Outstanding principal amount						$ 308,600,000	£ 250.0
Estimated fair value						334,900,000
Carrying value						$ 304,600,000
2023 VM Sterling Senior Notes | 2018
Debt Instrument [Line Items]
Redemption price			103.50%
2023 VM Sterling Senior Notes | 2019
Debt Instrument [Line Items]
Redemption price			102.333%
2023 VM Sterling Senior Notes | 2020
Debt Instrument [Line Items]
Redemption price			101.667%
2023 VM Sterling Senior Notes | 2021
Debt Instrument [Line Items]
Redemption price			100.00%
2023 VM Sterling Senior Notes | 2022
Debt Instrument [Line Items]
Redemption price			100.00%
2024 VM Dollar Senior Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			6.00%			6.00%	6.00%
Original issue amount						$ 500,000,000.0
Outstanding principal amount						500,000,000.0
Estimated fair value						513,100,000
Carrying value						$ 495,500,000
2024 VM Dollar Senior Notes [Member] | 2019
Debt Instrument [Line Items]
Redemption price			103.00%
2024 VM Dollar Senior Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			102.00%
2024 VM Dollar Senior Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			101.00%
2024 VM Dollar Senior Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			100.00%
2024 VM Dollar Senior Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.00%
2024 VM Sterling Senior Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			6.375%			6.375%	6.375%
Original issue amount | £							£ 300.0
Outstanding principal amount						$ 370,300,000	£ 300.0
Estimated fair value						393,000,000.0
Carrying value						$ 367,700,000
2024 VM Sterling Senior Notes [Member] | 2019
Debt Instrument [Line Items]
Redemption price			103.188%
2024 VM Sterling Senior Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			102.125%
2024 VM Sterling Senior Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			101.063%
2024 VM Sterling Senior Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			100.00%
2024 VM Sterling Senior Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM Euro Senior Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			4.50%			4.50%	4.50%
Original issue amount | €			€ 460.0
Outstanding principal amount			€ 460.0			$ 485,200,000
Estimated fair value						502,700,000
Carrying value						$ 479,800,000
2025 VM Euro Senior Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			102.25%
2025 VM Euro Senior Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			101.50%
2025 VM Euro Senior Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			100.75%
2025 VM Euro Senior Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM Euro Senior Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM Dollar Senior Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			5.75%			5.75%	5.75%
Original issue amount						$ 400,000,000.0
Outstanding principal amount						400,000,000.0
Estimated fair value						399,300,000
Carrying value						$ 396,400,000
2025 VM Dollar Senior Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			102.875%
2025 VM Dollar Senior Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			101.917%
2025 VM Dollar Senior Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			100.958%
2025 VM Dollar Senior Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM Dollar Senior Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
January 2021 VM Senior Secured Notes [Member]
Debt Instrument [Line Items]
Additional basis points used to determine redemption premium			25.00%			25.00%	25.00%
January 2021 VM Sterling Senior Secured Notes
Debt Instrument [Line Items]
Stated interest rate of debt			5.50%			5.50%	5.50%
Original issue amount | £							£ 628.4
Outstanding principal amount						$ 775,800,000	£ 628.4
Estimated fair value						860,600,000
Carrying value						$ 782,700,000
January 2021 VM Dollar Senior Secured Notes
Debt Instrument [Line Items]
Stated interest rate of debt			5.25%			5.25%	5.25%
Original issue amount						$ 447,900,000
Outstanding principal amount						447,900,000
Estimated fair value						475,300,000
Carrying value						$ 456,000,000.0
April 2021 VM Sterling Senior Secured Notes
Debt Instrument [Line Items]
Stated interest rate of debt			6.00%			6.00%	6.00%
Original issue amount | £							£ 1,100.0
Outstanding principal amount						$ 790,100,000	£ 640.0
Estimated fair value						824,600,000
Carrying value						$ 782,700,000
April 2021 VM Sterling Senior Secured Notes | 2017
Debt Instrument [Line Items]
Redemption price			103.00%
April 2021 VM Sterling Senior Secured Notes | 2018
Debt Instrument [Line Items]
Redemption price			101.50%
April 2021 VM Sterling Senior Secured Notes | 2019
Debt Instrument [Line Items]
Redemption price			100.00%
April 2021 VM Sterling Senior Secured Notes | 2020
Debt Instrument [Line Items]
Redemption price			100.00%
April 2021 VM Dollar Senior Secured Notes [Member] | 2017
Debt Instrument [Line Items]
Redemption price			102.688%
April 2021 VM Dollar Senior Secured Notes [Member] | 2018
Debt Instrument [Line Items]
Redemption price			101.344%
April 2021 VM Dollar Senior Secured Notes [Member] | 2019
Debt Instrument [Line Items]
Redemption price			100.00%
April 2021 VM Dollar Senior Secured Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM 5.5% Sterling Senior Secured Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			5.50%			5.50%	5.50%
Original issue amount | £							£ 430.0
Outstanding principal amount						$ 477,800,000	£ 387.0
Estimated fair value						495,700,000
Carrying value						$ 475,800,000
2025 VM 5.5% Sterling Senior Secured Notes [Member] | 2019
Debt Instrument [Line Items]
Redemption price			102.75%
2025 VM 5.5% Sterling Senior Secured Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			101.833%
2025 VM 5.5% Sterling Senior Secured Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM 5.5% Sterling Senior Secured Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM 5.5% Sterling Senior Secured Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM 5.5% Sterling Senior Secured Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM 5.125% Sterling Senior Secured Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			5.125%			5.125%	5.125%
Original issue amount | £							£ 300.0
Outstanding principal amount						$ 370,300,000	£ 300.0
Estimated fair value						380,800,000
Carrying value						$ 367,000,000.0
2025 VM 5.125% Sterling Senior Secured Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			102.563%
2025 VM 5.125% Sterling Senior Secured Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			101.708%
2025 VM 5.125% Sterling Senior Secured Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			100.854%
2025 VM 5.125% Sterling Senior Secured Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM 5.125% Sterling Senior Secured Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
2025 VM Dollar Senior Secured Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			5.50%			5.50%	5.50%
Original issue amount						$ 425,000,000.0
Outstanding principal amount						425,000,000.0
Estimated fair value						432,400,000
Carrying value						$ 423,300,000
2026 VM 5.25% Dollar Senior Secured Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			5.25%			5.25%	5.25%
Original issue amount						$ 1,000,000,000.0
Outstanding principal amount						1,000,000,000.0
Estimated fair value						991,300,000
Carrying value						$ 1,002,000,000.0
2026 VM 5.25% Dollar Senior Secured Notes [Member] | 2020
Debt Instrument [Line Items]
Redemption price			102.625%
2026 VM 5.25% Dollar Senior Secured Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			101.313%
2026 VM 5.25% Dollar Senior Secured Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			100.656%
2026 VM 5.25% Dollar Senior Secured Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.00%
2026 VM 5.25% Dollar Senior Secured Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
2026 VM 5.5% Dollar Senior Secured Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			5.50%			5.50%	5.50%
Original issue amount						$ 750,000,000.0
Outstanding principal amount						750,000,000.0
Estimated fair value						751,400,000
Carrying value						$ 742,800,000
2026 VM 5.5% Dollar Senior Secured Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			102.75%
2026 VM 5.5% Dollar Senior Secured Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			101.375%
2026 VM 5.5% Dollar Senior Secured Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.688%
2026 VM 5.5% Dollar Senior Secured Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
2027 VM Senior Secured Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			4.875%			4.875%	4.875%
Original issue amount | £							£ 525.0
Outstanding principal amount						$ 648,100,000	£ 525.0
Estimated fair value						637,600,000
Carrying value						$ 645,600,000
2027 VM Senior Secured Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			102.438%
2027 VM Senior Secured Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			101.219%
2027 VM Senior Secured Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			100.609%
2027 VM Senior Secured Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
2029 VM Senior Secured Notes [Member] | 2021
Debt Instrument [Line Items]
Redemption price			103.125%
2029 VM Senior Secured Notes [Member] | 2022
Debt Instrument [Line Items]
Redemption price			102.083%
2029 VM Senior Secured Notes [Member] | 2023
Debt Instrument [Line Items]
Redemption price			101.042%
2029 VM Senior Secured Notes [Member] | 2024 and thereafter
Debt Instrument [Line Items]
Redemption price			100.00%
2029 VM Sterling Senior Secured Notes [Member]
Debt Instrument [Line Items]
Stated interest rate of debt			6.25%			6.25%	6.25%
Original issue amount | £							£ 400.0
Outstanding principal amount						$ 493,800,000	400.0
Estimated fair value						520,300,000
Carrying value						494,800,000
Long-term Debt [Member] | VM Notes [Member]
Debt Instrument [Line Items]
Gains (losses) on extinguishment of debt				(44,300,000)	$ 32,300,000
Write off of deferred financing costs				28,600,000	15,600,000
Payment for debt redemption premium				10,700,000	123,000,000.0
Write-off of unamortized debt discount (premium)				4,200,000	(170,900,000)
Third-party debt modification costs				$ 800,000	$ 0
Long-term Debt [Member] | April 2021 VM Sterling Senior Secured Notes
Debt Instrument [Line Items]
Original issue amount						$ 1,222,200,000	£ 990.0
Extinguishment of debt	$ 432,100,000	£ 350.0
Long-term Debt [Member] | April 2021 VM Dollar Senior Secured Notes [Member]
Debt Instrument [Line Items]
Extinguishment of debt	$ 900,000,000.0