Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount

No definition available.

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- Definition

Number of Institutional Investors that Purchased Warrant

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Approved Payroll Deduction to Purchase Shares, Percentage

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangements by Share-based Payment Award, Options, Tax Withholding And Exercises in Period, Weighted Average Exercise Price

+ References

No definition available.

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- Definition

Shareholder Rights Plan, Percentage Of Share Ownership Defining Acquiring Person

+ References

No definition available.

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- Definition

The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ 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
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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- Definition

Face amount per share of no-par value preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

+ Details

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ 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.

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

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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.

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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).

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-Paragraph 2
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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

Number of share instruments newly issued under a share-based compensation plan.

+ References

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 2
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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Paragraph 2
-Subparagraph (c)
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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ 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
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-Name Accounting Standards Codification
-Topic 210
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Stockholders' Equity and Stock Plans - Narrative (Details) $ / shares in Units, $ in Thousands		1 Months Ended		12 Months Ended
	Jan. 19, 2018 $ / shares	Sep. 30, 2015 $ / shares shares	Nov. 30, 2011 investor	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) shares	Jul. 23, 2017 $ / shares shares	Jul. 06, 2017	May 16, 2017 shares	Nov. 01, 2011 $ / shares shares	May 11, 2010 shares	Jul. 01, 2007 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares withheld for tax withholding and exercise of options				12,208	0	0
Value of shares withheld for tax withholding and exercise of options \| $				$ 801
Shares withheld for tax withholding and exercise of options, weighted average price (usd per share) \| $ / shares				$ 65.63
Total compensation cost for share-based payment arrangements \| $				$ 1,300	$ 994	$ 636
Share-based compensation income tax benefit recognized \| $				293	318	194
Unrecognized compensation expense \| $				$ 1,500
Period for recognizing unrecognized compensation expense				2 years 1 month 6 days
Excess tax benefits recorded as a reduction to income tax expense \| $				$ 214
Tax benefit realized from disqualifying dispositions of incentive stock options \| $					$ 70	49
Percentage of share ownership defining an acquiring person								10.00%
Preferred stock, no par value (in dollars per share) \| $ / shares				$ 0	$ 0
Preferred stock, authorized (in shares)				5,000,000	5,000,000
Number of common stock shares authorized to be purchased by warrant		157,711								154,242
Number of institutional investors that purchased warrant \| investor			2
Net issuance of shares of common stock from cashless exercise (in shares)		70,591
Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends declared per common share (usd per share) \| $ / shares	$ 0.29
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total grant-date fair value of option shares vested \| $				$ 449	$ 282	202
Stock options \| During 2006 through 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				5 years
Expiration period of grants				10 years
Stock options \| During 2006 through 2014 \| Vesting Rate, Year One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| During 2006 through 2014 \| Vesting Rate, Year Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| During 2006 through 2014 \| Vesting Rate, Year Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| During 2006 through 2014 \| Vesting Rate Year Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| During 2006 through 2014 \| Vesting Rate Year Five
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| Prior to 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				4 years
Expiration period of grants				7 years
Stock options \| Prior to 2016 \| Immediately Upon Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| Prior to 2016 \| Vesting Rate, Year One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| Prior to 2016 \| Vesting Rate, Year Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| Prior to 2016 \| Vesting Rate, Year Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| Prior to 2016 \| Vesting Rate Year Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Stock options \| After 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				33.00%
Award vesting period				3 years
Expiration period of grants				10 years
Stock options \| During 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				33.00%
Award vesting period				3 years
Expiration period of grants				10 years
Restricted stock award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total grant-date fair value of option shares vested \| $				$ 473	$ 380	$ 262
Restricted stock award \| During 2006 through 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				5 years
Expiration period of grants				10 years
Restricted stock award \| During 2006 through 2014 \| Vesting Rate, Year One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Restricted stock award \| During 2006 through 2014 \| Vesting Rate, Year Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Restricted stock award \| During 2006 through 2014 \| Vesting Rate, Year Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Restricted stock award \| During 2006 through 2014 \| Vesting Rate Year Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Restricted stock award \| During 2006 through 2014 \| Vesting Rate Year Five
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				20.00%
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				3 years
Minimum \| Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				0.00%
Maximum \| Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage				200.00%
Director Stock Plan, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares approved to be issued in common stock											150,000
Number of shares available for future grants under plan				110,433
Employee Stock Purchase Plan, 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares approved to be issued in common stock												200,000
Number of shares available for future grants under plan				192,453
Discount from closing market price at end of each quarter				500.00%
Employee Stock Purchase Plan, 2007 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approved payroll deduction to purchase shares, percentage				100.00%
Employee Stock Purchase Plan, 2007 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Approved payroll deduction to purchase shares, percentage				1500.00%
The 2017 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future grants under plan				108,981					118,668
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of warrant to purchase common stock (in shares) \| $ / shares		$ 26.63
Common Stock \| U.S. Treasury Capital Purchase Program (TCPP)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of warrant to purchase common stock (in shares) \| $ / shares										$ 27.23
Common Stock \| Director Stock Plan, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares awarded in period from plan				2,878	4,607	5,295
Series A Junior Participating Preferred Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, no par value (in dollars per share) \| $ / shares				$ 0
Preferred stock, authorized (in shares)				1,000,000
Exercise price of warrant to purchase common stock (in shares) \| $ / shares							$ 9,000
Number of shares each right entitles holder to purchase							0.01