Stockholders' Deficit - Summary of Stock Options and RSUs Outstanding and Unrecognized Compensation Cost (Details) shares in Millions, $ in Millions	Sep. 30, 2016 USD ($) shares
Employee stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares) \| shares	3.2
Compensation cost not yet recognized \| $	$ 8.3
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares) \| shares	5.6
Compensation cost not yet recognized \| $	$ 52.8

Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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+ References

No definition available.

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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=6415400&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=6415400&loc=d3e5070-113901

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