Represents Number of shares sold to underwriters.

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- Definition

Represents stock repurchase program number of shares authorized to be repurchased under prior program.

+ References

No definition available.

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- Definition

Stockholders Equity [Line Items]

+ 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
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-SubTopic 10
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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 cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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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

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.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

+ 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.

+ References

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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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- Definition

Description of the stock split arrangement. Also provide the retroactive effect given by a stock split that occurs after the balance date but before the release of financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Stock Split
-URI http://asc.fasb.org/extlink&oid=6525746

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-Subparagraph (SAB Topic 4.C)
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STOCKHOLDERS' EQUITY (Detail Textuals) - USD ($)		1 Months Ended	12 Months Ended
STOCKHOLDERS' EQUITY (Detail Textuals) - USD ($)	Apr. 01, 2015	Jun. 30, 2014	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015	Dec. 31, 2015
Stockholders Equity [Line Items]
Stock split of common stock	two-for-one
Number of common share sold		3,450,000
Number of shares sold to underwriters		450,000
Public offering price per share (in dollars per share)		$ 38.82
Net proceed from offering		$ 128,700,000			$ 128,686,000
Number of shares authorized to be repurchased under prior program						3,750,000
Number of increased authorized shares to be repurchased						5,000,000
Proceeds from exercise of stock options			$ 260,000	$ 417,000	729,000
Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Shares available for grant			1,504,807
Restricted Stock Units (RSUs) \| Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Recognized compensation expense			$ 16,800,000	15,600,000	11,600,000
Unrecognized stock compensation related to unvested option awards			$ 40,700,000	42,000,000	32,200,000
Restricted Stock Units (RSUs) \| Minimum
Stockholders Equity [Line Items]
Vesting and exercise period of awards			3 years
Restricted Stock Units (RSUs) \| Minimum \| Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Vesting and exercise period of awards			3 years
Restricted Stock Units (RSUs) \| Maximum
Stockholders Equity [Line Items]
Vesting and exercise period of awards			5 years
Restricted Stock Units (RSUs) \| Maximum \| Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Vesting and exercise period of awards			5 years
Stock Options
Stockholders Equity [Line Items]
Weighted average remaining term for stock options outstanding			1 year 8 months 12 days
Aggregate intrinsic value for stock options outstanding			$ 4,300,000
Proceeds from exercise of stock options			260,000	417,000
Intrinsic value of stock options exercised			936,000	1,700,000
Recognized compensation expense			$ 126,000	$ 153,000	$ 541,000
Stock Options \| Maximum \| Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Vesting and exercise period of awards			10 years