Equity Compensation Plans - Summary of Stock Option Activity by Range of Exercise Price (Details) shares in Thousands	12 Months Ended
Dec. 31, 2016 $ / shares shares
Schedule Of Stock Options [Line Items]
Awards Outstanding, Number of Awards Outstanding \| shares	4,184
Awards Outstanding, Weighted Average Years of Remaining Contractual Life	7 years 3 months 18 days
Awards Outstanding, Weighted Average Exercise Price	$ 1.64
Awards Exercisable, Number of Awards Exercisable \| shares	1,846
Awards Exercisable, Weighted Average Exercise Price	$ 1.37
$0.00 - $1.00
Schedule Of Stock Options [Line Items]
Range of Exercise Prices, lower limit	0.00
Range of Exercise Prices, upper limit	$ 1.00
Awards Outstanding, Number of Awards Outstanding \| shares	2,002
Awards Outstanding, Weighted Average Years of Remaining Contractual Life	6 years 7 months 6 days
Awards Outstanding, Weighted Average Exercise Price	$ 1.00
Awards Exercisable, Number of Awards Exercisable \| shares	1,080
Awards Exercisable, Weighted Average Exercise Price	$ 1.00
$1.01 - $2.00
Schedule Of Stock Options [Line Items]
Range of Exercise Prices, lower limit	1.01
Range of Exercise Prices, upper limit	$ 2.00
Awards Outstanding, Number of Awards Outstanding \| shares	1,418
Awards Outstanding, Weighted Average Years of Remaining Contractual Life	7 years 1 month 6 days
Awards Outstanding, Weighted Average Exercise Price	$ 1.30
Awards Exercisable, Number of Awards Exercisable \| shares	710
Awards Exercisable, Weighted Average Exercise Price	$ 1.30
$2.01 - $10.00
Schedule Of Stock Options [Line Items]
Range of Exercise Prices, lower limit	2.01
Range of Exercise Prices, upper limit	$ 10.00
Awards Outstanding, Number of Awards Outstanding \| shares	685
Awards Outstanding, Weighted Average Years of Remaining Contractual Life	9 years 9 months 18 days
Awards Outstanding, Weighted Average Exercise Price	$ 2.98
Awards Exercisable, Number of Awards Exercisable \| shares	21
Awards Exercisable, Weighted Average Exercise Price	$ 4.14
$10.01 - $16.00
Schedule Of Stock Options [Line Items]
Range of Exercise Prices, lower limit	10.01
Range of Exercise Prices, upper limit	$ 16.00
Awards Outstanding, Number of Awards Outstanding \| shares	79
Awards Outstanding, Weighted Average Years of Remaining Contractual Life	8 years 3 months 18 days
Awards Outstanding, Weighted Average Exercise Price	$ 12.63
Awards Exercisable, Number of Awards Exercisable \| shares	35
Awards Exercisable, Weighted Average Exercise Price	$ 12.64

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ 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)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average remaining contractual term of outstanding stock options, 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Schedule of stock options.

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