Deferred comopnesation agreement with individual, annual grant per nonemployee director

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- Definition

Deferred compensation aggrangement with individual, nonemployee director, former plan, term

+ References

No definition available.

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- Definition

Deferred compensation arrangement with individual, nonemployee director, annual grant per director, former plan

+ References

No definition available.

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- Definition

Deferred compensation arrangement with individual, nonemployee director, service period, former plan

+ References

No definition available.

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- Definition

Deferred compensation arrangement with individual, nonemployee directors, vesting period

+ References

No definition available.

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- Details

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- Definition

Employee stock purchase plan, cumulative shares purchased

+ References

No definition available.

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- Definition

Employee stock purchase plan, weighted average purchase price of shares purchased

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Aggregate Intrinsic Value

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award, number of employees participating

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Unrecognized Compensation Cost

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Market Price, Purchase Date

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Stock Options, Awarded, Outstanding, Number

+ References

No definition available.

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- Definition

Stock Awarded During Period, Shares, Stock Appreciation Rights

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No definition available.

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- Definition

Stock based compensation, shares purchased under Employee Stock Purchase Plan

+ 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

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: 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=6793087&loc=d3e301413-122809

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ 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

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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

The discount rate from market value on purchase date that participants pay for shares.

+ 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

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- Definition

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

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

Expected term of share-based compensation awards, 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 S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(i)

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The range of expected volatilities used and the weighted-average expected volatility for an entity using a valuation technique with different volatilities during the contractual term.

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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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- 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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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

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

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: 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 3: 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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ 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

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options outstanding.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

+ References

No definition available.

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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Stock-Based Compensation (Details) (USD $)	12 Months Ended
Stock-Based Compensation (Details) (USD $)	Dec. 31, 2012 Rate	Dec. 31, 2011 Rate	Dec. 31, 2010 Rate
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares authorized	10,000,000
Share-based compensation, number of shares available for grant	865,704
Stock based compensation, shares purchased under Employee Stock Purchase Plan	3,897,974
Deferred compensation arrangement with individual, nonemployee directors, vesting period	P5Y
Deferred compensation arrangement with individual, nonemployee director, service period, former plan	P6M
Salaries, Wages and Officers' Compensation [Abstract]
Compensation expense, all share-based payment plans	$ 1,508,000	$ 1,349,000	$ 1,224,000
Income tax benefit	383,000,000	329,000,000	292,000,000
Employee Stock Purchase Plan [Abstract]
Shares purchased during the year	136,947,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Volatility rate	11.70%	11.90%	12.20%
Risk-free interest rate	1.60%	2.90%	3.00%
Expected dividend yield	1.50%	1.50%	1.50%
Expected life of awards (years)	9 years 1 month 6 days	8 years 10 months 24 days	9 years 4 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning balance	1,110,785
Granted, Stock Options	0
Exercised	341,531
Forfeited	8,000
Outstanding, ending balance	761,254	1,110,785
Exercisable, ending balance	639,654
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding, weighted average exercise price, beginning balance	$ 10.62
Granted, weighted average exercise price	$ 0
Exercised, weighted average exercise price	$ 9.01
Forfeited, weighted average exercise price	$ 7.91
Outstanding, weighted average exercise price, ending balance	$ 11.38	$ 10.62
Exercisable, weighted average exercise price, ending balance	$ 10.44
Outstanding, weighted average remaining contractual life (years)	3 years 9 months 7 days
Exercisable, weighted average remaining contractual life (years)	3 years 29 days
Outstanding, unrecognized compensation cost	8,660,000
Outstanding, aggregate intrinsic value	7,174,000
Exercisable, aggregate intrinisic value	6,630,000
Number outstanding	761,254.000
Number exercisable	639,654.000
Employee Stock Purchase Plan [Member]
Salaries, Wages and Officers' Compensation [Abstract]
Compensation expense, all share-based payment plans	415,000	410,000	389,000
Employee Stock Purchase Plan [Abstract]
Employee stock purchase, discount from market price, purchase date	15.00%
Number of employees participating	1,157	1,272	1,230
Shares purchased during the year	136,947	150,253	156,381
Weighted-average per share purchase price paid	$ 17.20	$ 15.46	$ 14.11
Cumulative shares purchased since 1982	8,517,782	8,380,835	8,230,582
Employee Stock Purchase Plan [Member]
Employee Stock Purchase Plan [Abstract]
Employee stock purchase plan, service period	1 year
Employee stock purchase plan, percentage of market price, purchase date	85.00%
Employee stock purchase, discount from market price, purchase date	15.00%
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vesting period	10 years
Salaries, Wages and Officers' Compensation [Abstract]
Compensation expense, all share-based payment plans	166,000	269,000	361,000
Employee Stock Purchase Plan [Abstract]
Stock options, awarded, outstanding	505,167
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred comopnesation agreement with individual, annual grant per nonemployee director	3,000
Salaries, Wages and Officers' Compensation [Abstract]
Compensation expense, all share-based payment plans	283,000	185,000	105,000
Employee Stock Purchase Plan [Abstract]
Stock appreciation rights, awarded	105,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, beginning balance	210,188
Granted	105,000
Forfeited	0
Vested	57,371
Unvested, ending balance	257,817	210,188
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, beginning balance	$ 3.47
Granted, weighted average award date value	$ 2.70
Forfeited, weighted average award date value	$ 0
Vested, weighted average award date value	$ 3.43
Unvested, weighted average award date value, ending balance	$ 3.17	$ 3.47
Weighted average remaining contractual life (years)	2 years 9 months 18 days
Unrecognized compensation cost	573,000
Aggregate intrinsic value	5,363,000
Employee SSARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, ending balance	218,400
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, ending balance	$ 3.31
Weighted average remaining contractual life (years)	2 years 8 months 12 days
Unrecognized compensation cost	495,000
Aggregate intrinsic value	4,543,000
Nonemployee Director SSARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, ending balance	39,417
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, ending balance	$ 2.34
Weighted average remaining contractual life (years)	3 years 4 months 24 days
Unrecognized compensation cost	78,000
Aggregate intrinsic value	820,000
Restricted Stock Units (RSUs) [Member]
Salaries, Wages and Officers' Compensation [Abstract]
Compensation expense, all share-based payment plans	644,000	485,000	369,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, beginning balance	113,908
Granted	23,058
Forfeited	0
Vested	58,313
Unvested, ending balance	78,653	113,908
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested, weighted average award date value, beginning balance	$ 15.15
Granted, weighted average award date value	$ 19.41
Forfeited, weighted average award date value	$ 0
Vested, weighted average award date value	$ 14.52
Unvested, weighted average award date value, ending balance	$ 16.87	$ 15.15
Weighted average remaining contractual life (years)	3 years 10 months 24 days
Unrecognized compensation cost	626,000
Aggregate intrinsic value	$ 1,636,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares available for grant	3,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Number outstanding	747,920.00
Weighted average remaining contractual life (years)	3 years 9 months 26 days
Outstanding options, weighted average exercise price	$ 11.32
Number exercisable	626,320
Exercisable options, weighted average exercise price	$ 10.35
Employee Stock Option [Member] \| $6.75 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Lower range limit	$ 6.75
Upper range limit	$ 6.75
Number outstanding	256,087
Weighted average remaining contractual life (years)	11 months 5 days
Outstanding options, weighted average exercise price	$ 6.75
Number exercisable	256,087
Exercisable options, weighted average exercise price	$ 6.75
Employee Stock Option [Member] \| $11.25 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Lower range limit	$ 11.25
Upper range limit	$ 11.25
Number outstanding	251,433
Weighted average remaining contractual life (years)	3 years 5 months 5 days
Outstanding options, weighted average exercise price	$ 11.25
Number exercisable	251,433
Exercisable options, weighted average exercise price	$ 11.25
Employee Stock Option [Member] \| $16.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Lower range limit	$ 16.00
Upper range limit	$ 16.00
Number outstanding	131,000
Weighted average remaining contractual life (years)	6 years 10 months 2 days
Outstanding options, weighted average exercise price	$ 16.00
Number exercisable	75,400
Exercisable options, weighted average exercise price	$ 16.00
Employee Stock Option [Member] \| $16.60 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Lower range limit	$ 16.60
Upper range limit	$ 16.60
Number outstanding	109,400
Weighted average remaining contractual life (years)	7 years 10 months 2 days
Outstanding options, weighted average exercise price	$ 16.60
Number exercisable	43,400
Exercisable options, weighted average exercise price	$ 16.60
Director Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation aggrangement with individual, nonemployee director, former plan, term	P6Y
Deferred compensation arrangement with individual, nonemployee director, annual grant per director, former plan	4,000
Director Stock Option [Member] \| $12.95 to $16.40
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Lower range limit	$ 12.95
Upper range limit	$ 16.40
Number outstanding	13,334
Weighted average remaining contractual life (years)	10 months 28 days
Outstanding options, weighted average exercise price	$ 14.33
Number exercisable	13,334
Exercisable options, weighted average exercise price	$ 14.33