v3.10.0.1

(Loss) Earnings Per Share - Additional Information (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive effect on calculation of diluted earnings per common share attributable to outstanding stock-based awards (in shares)	0.3	0.6	0.3	0.3
Options | Class A
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive effect on calculation of diluted earnings per common share attributable to outstanding stock-based awards (in shares)	2.9	1.7	2.9	1.6

X

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Definition

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+ References

No definition available.

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