Payroll deduction percentage of closing market price of common stock.

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=6415400&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=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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Balance Type:	debit
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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Period Type:	instant

- 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=6415400&loc=d3e5070-113901

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Description of the plan, including the basis for determining contributions, the employee groups covered, and the nature and effect of significant matters affecting comparability of information for all periods presented. For leveraged ESOPs and pension reversion ESOPs, the description generally includes the basis for releasing shares and how dividends on allocated and unallocated shares are used.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929

+ Details

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ 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)(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.

+ References

No definition available.

+ Details

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- Definition

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

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

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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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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Balance Type:	na
Period Type:	instant

- Definition

Percentage of vesting of share-based compensation awards.

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

+ Details

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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	instant

- Definition

Number of options vested.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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- Definition

Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

+ References

+ Details

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Balance Type:	credit
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- Details

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- Details

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- Details

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Stock Based Compensation Plans - Additional Information (Details) - USD ($)								1 Months Ended			3 Months Ended	6 Months Ended		12 Months Ended
	Jan. 13, 2016	Nov. 23, 2015	Jul. 09, 2015	Jan. 08, 2015	Jan. 07, 2015	Oct. 07, 2014	Nov. 19, 2013	Jul. 31, 2015	Mar. 31, 2014	Nov. 30, 2013	Mar. 31, 2014	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, granted							145,824							825,227	269,676
Shares issued												820,529		820,529	196,882	109,369
Shares awarded , fair market value per share							$ 6.49							$ 26.27	$ 15.72
Compensation expense														$ 5,600,000	$ 3,100,000	$ 1,200,000
Fully vested common stock granted														183,245	182,163
Fair value on award date per share														$ 27.34	$ 7.14
Shares price per share															$ 5.24
Effect of employee stock purchase plan														$ 554,000
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense														$ 222,000	$ 0	0
Employee stock purchase plan, purchase price, Description														On the exercise date (the last trading day of each option period), the cumulative amount deducted from each participant’s salary during that option period will be used to purchase the maximum number of shares of the Company’s common stock at a purchase price equal to the lesser of (i) 85% of the closing market price of the Company’s common stock as quoted on the New York Stock Exchange on the exercise date or (ii) 85% of the closing market price of the Company’s common stock as quoted on the New York Stock Exchange on the grant date, subject to certain limitations and restrictions.
Payroll deduction percentage of closing market price of common stock								85.00%
Effect of employee stock purchase plan, shares								12,637
Shares price per share								$ 25.68
Effect of employee stock purchase plan												$ 200,000	$ 300,000
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, granted					400,000	158,000
Unrecognized compensation expenses												$ 19,000,000		$ 19,000,000
Weighted average life of remaining vesting period														2 years 7 months 6 days
Five Non Employee Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense											$ 200,000			$ 400,000
Fully vested common stock granted				2,544					5,834
Fair value on award date per share				$ 29.37					$ 8.12
2007 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance												3,927,798		3,927,798
Stock options, granted														0	0
Stock options, outstanding												0		0	0
2007 Stock Incentive Plan \| Restricted Stock \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, granted	110,000
2007 Stock Incentive Plan \| COO, Vice President of Business Development and Marketing \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, granted										145,824
Shares vested															36,455
Shares issued															109,369
Shares awarded , fair market value per share															$ 6.49
Compensation expense															$ 700,000	200,000
Additional compensation expense															$ 800,000	$ 100,000
2007 Stock Incentive Plan \| Five Non Employee Directors \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fully vested common stock granted	30,000
2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for issuance												1,571,120		1,571,120
2014 Equity Incentive Plan \| Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, granted		405,000	3,174
Vested percentage			75.00%
2014 Equity Incentive Plan \| Restricted Stock \| Subsequent Event
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, granted	140,000