Share-based Compensation (Awards Outstanding and Exercisable) (Details)	Jun. 30, 2017 $ / shares shares
Liberty Global Group [Member] \| Options, SARs and PSARs [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	15,772,744
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 32.27
Options exercisable (in shares)	8,778,178
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 29.62
Liberty Global Group [Member] \| Options, SARs and PSARs [Member] \| Common Class C [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	37,673,600
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 30.06
Options exercisable (in shares)	23,636,492
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 27.44
Liberty Global Group [Member] \| Restricted Stock Units (RSUs) [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	680,875
Liberty Global Group [Member] \| Restricted Stock Units (RSUs) [Member] \| Common Class C [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	1,353,264
Liberty Global Group [Member] \| PSUs / PGUs [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	2,425,135
Liberty Global Group [Member] \| PSUs / PGUs [Member] \| Common Class C [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	4,857,495
LiLAC Group [Member] \| Options, SARs and PSARs [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	2,551,821
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 31.61
Options exercisable (in shares)	1,220,756
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 33.54
LiLAC Group [Member] \| Options, SARs and PSARs [Member] \| Common Class C [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	5,918,044
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 31.60
Options exercisable (in shares)	3,253,819
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 32.65
LiLAC Group [Member] \| Restricted Stock Units (RSUs) [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	191,990
LiLAC Group [Member] \| Restricted Stock Units (RSUs) [Member] \| Common Class C [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	393,870
LiLAC Group [Member] \| PSUs / PGUs [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	432,405
LiLAC Group [Member] \| PSUs / PGUs [Member] \| Common Class C [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	864,853

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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