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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- References

No definition available.

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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

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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

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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Share-Based Compensation (Unrecognized) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Apr. 30, 2016
Unrecognized share-based compensation
Unrecognized share-based compensation cost	$ 11,200,000
Restricted stock awards
Unrecognized share-based compensation
Unrecognized share-based compensation cost - RSA	$ 1,000
Unrecognized share-based compensation - Weighted average period	3 years 2 months 12 days
Stock options
Unrecognized share-based compensation
Unrecognized share-based compensation cost - Stock options	$ 11,200,000
Unrecognized share-based compensation - Weighted average period	1 month 6 days
Purchased under the ESPP	2,023,700	305,278
ESPP
Unrecognized share-based compensation
Common stock reserved for issuance (in shares)			150,000
Purchased under the ESPP	0