Stock-Based Compensation (Restricted Stock Units Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) $ / shares
Unvested restricted stock awards
Number of Shares
Grant date fair value \| $ / shares	$ 0.00
Restricted Stock Units (RSUs)
Number of Shares
Unrecognized employee stock-based compensation \| $	$ 35.6
Unrecognized employee stock-based compensation, period for recognition	3 years 3 months
Grant date fair value \| $ / shares	$ 6.01
Fair value of restricted stock unit \| $	$ 0.7
Intrinsic value of nonvested unit \| $	$ 28.9
Restricted Stock Units (RSUs) \| Weighted Average Grant Date Value Per Share
Number of Shares
Grant date fair value \| $ / shares	$ 6.01

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ 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 (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

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- Definition

Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

+ References

No definition available.

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