v3.10.0.1

Equity (Schedule of Outstanding Share-Based Compensation Awards) (Details) - shares	Dec. 31, 2018	Dec. 31, 2017
Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common reserved for issuance (in shares)	11,099,593
Options | Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)	580,254	580,481
Options | Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)	2,667,506	2,725,566
SARs | Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common reserved for issuance (in shares)	15,308,562
SARs | Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards outstanding (in shares)	34,401,980	31,305,136
Common reserved for issuance (in shares)	34,401,980
PSUs, PGUs, RSUs | Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common reserved for issuance (in shares)	3,487,018
PSUs, PGUs, RSUs | Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common reserved for issuance (in shares)	6,976,788

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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+ References

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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