Share based compensation arrangement by share based payment award number of installments.

No definition available.

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- Definition

Unrecognized cost of unvested 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 (i)
-URI http://asc.fasb.org/extlink&oid=6415400&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

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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

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

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-Publisher FASB
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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
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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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Equity-Based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average fair value on the date of grant of stock options granted	$ 0.96	$ 2.17	$ 5.91
Stock-based compensation expense for non-vested equity-based compensation	$ 2,600,000
Stock based compensation expense, recognition period		18 months
End of period, share price	$ 4.21
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	4 years
Restricted Stock [Member] \| Stock Vesting, One Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage	25.00%
Restricted Stock [Member] \| Stock Vesting, Two Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage	25.00%
Restricted Stock [Member] \| Stock Vesting, Three Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage	25.00%
Restricted Stock [Member] \| Stock Vesting, Four Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage	25.00%
2010 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	4 years
Number of shares authorized	1,900,000
Number of shares available for grant	441,000
Options exercised (in shares)	0	0	5,000
Intrinsic value of shares exercised			$ 18,000
Number of options outstanding and exercisable (in shares)	1,000,855	820,471	631,846	660,471
2010 Equity Award Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	1 year
2010 Equity Award Plan [Member] \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	15 years
2000 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant		0
Weighted average remaining contractual life	9 years 6 months
Options exercised (in shares)	182,500	473,472	601,800
Intrinsic value of shares exercised	$ 300,000	$ 1,600,000	$ 5,800,000
Number of options outstanding and exercisable (in shares)	1,170,925	1,356,375	1,868,597	2,472,147
2000 Equity Award Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	3 years
Award vesting period	1 year
2000 Equity Award Plan [Member] \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	4 years
Expiration period	15 years
1991 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options exercised (in shares)	0	127,000	0
Intrinsic value of shares exercised		$ 200,000
Number of options outstanding and exercisable (in shares)	0
1991 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized	800,000
Number of shares available for grant	44,000