Common stock fair market value per share.

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- Definition

Liability reclassified to additional paid in capital.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

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.

+ 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)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&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.

+ References

No definition available.

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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

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- Definition

Number of options vested.

+ References

No definition available.

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Stock-based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Early Exercise Of Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options, vested			1,522,826
Liability reclassified to additional paid-in-capital	$ 4.1		$ 4.1
Number of options, Unvested	0		0
Service-based Vesting Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair market value of common stock, per share	$ 22.55		$ 22.55
Unrecognized stock-based compensation cost	$ 8.3		$ 8.3
Unrecognized stock-based compensation cost, expected weighted-average period of recognition			3 years 2 months 13 days
Service-based Vesting Options \| Selling, General and Administrative Expenses
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation cost	$ 0.7	$ 2.6	$ 1.8	$ 3.7
Performance-based and Market-based Vesting Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair market value of common stock, per share	$ 22.55		$ 22.55
Stock-based compensation cost	$ 1.1	1.5	$ 2.9	1.5
Unrecognized stock-based compensation cost	$ 1.8		$ 1.8
Unrecognized stock-based compensation cost, expected weighted-average period of recognition			7 months 7 days
Restricted Stock Awards ("RSAs")
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unvested RSAs outstanding	302,200		302,200
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation cost	$ 2.0	$ 0.1	$ 5.0	$ 0.1
Unrecognized stock-based compensation cost, expected weighted-average period of recognition			3 years 2 months 13 days
Unvested RSAs outstanding	1,247,071		1,247,071		586,224
Unrecognized stock-based compensation cost	$ 24.9		$ 24.9